A Portrait of America

1.

American Demographic Growth

The American colonies, while still sparsely populated through much of the 1700s, were nevertheless recognized as having tremendous potential for demographic growth, wealth, and power. In his 1776 book, An Inquiry into the Nature and Causes of the Wealth of Nations, Scottish philosopher and economist Adam Smith noted:

But though North America is not yet so rich as England, it is much more thriving, and advancing with much greater rapidity to the greater acquisition of riches. The most decisive mark of the prosperity of any country is the increase in the number of its inhabitants. . . . Nor in the present times is this increase principally owing to the continued importation of new inhabitants, but to the great multiplication of the species. . . . Labor is there so well rewarded that a numerous family of children, rather than being a burthen, is a source of opulence and prosperity to the parents. . . . Notwithstanding the great increase occasioned by such early marriages, there is a continual complaint of the scarcity of hands in North America.

The territorial and demographic growth of the United States has historically also been accompanied by considerable individual social and economic mobility. American culture is infused with a deep egalitarian spirit and admiration of self-made men and women. This is represented by the creed of "American exceptionalism"-first described by Alexis de Tocqueville in the 1830s. In this view, there is a unique American ideology based on liberty, egalitarianism, individualism, populism, and laissez-faire that has fostered mobility.

American exceptionalism, as the term was originally conceived, meant not necessarily that the country was better than others but mainly that it was different. Seymour Martin Lipset, a well-known political scientist and sociologist, argued in a 1996 book on the topic that this rugged individualism marked a strong departure from the tradition-bound order of the Old European World. "Americans remain much more individualistic, meritocratic-oriented, and anti-statist than peoples everywhere." In his view these attributes have promoted entrepreneurship and economic growth. This is perhaps best represented in the recent past by the ascendency of Silicon Valley. Steve Jobs was an iconoclastic figure in this respect-he saw himself as a rebel against authority and urged people to "Think Different." Many argue that this emphasis on individualism and innovation helps explain why the United States today has the world's largest economy and one of the highest GDPs per capita.

Lipset also argued, however, that this emphasis on individualism, and by extension nonconformity, has a downside if completely unchecked by social mores that promote the good of the community. An ethos centered on individualism means that inequality is more widely accepted in the United States than in other countries. This helps explain why U.S. poverty rates are higher and average life expectancies are lower than those in other rich countries, not to mention America's large prison population, litigiousness, and low levels of voter participation.

Before delving into the contemporary state of social and economic affairs in the United States, this chapter first reviews America's demographic history-its ascent from a group of sparsely settled colonies on the eastern seaboard of the continent to one of the world's superpowers today. I focus on the roles that changing patterns of fertility, mortality, and immigration played in this growth and some of America's commonalities with and differences from other Western countries. Having a grasp of this "exceptional" history-and its demographic origins-is necessary for understanding our changing population today.

America's Demographic Transition

The first U.S. census was taken 1790-not long after the founding of the nation. At the time, the population of the thirteen original states and the territories that would become Vermont, Kentucky, Tennessee, and Maine came to just 3.9 million people. Over the next seven decades the United States grew at a clip of over 30 percent per decade, such that by 1860, on the eve of the Civil War, there were 31.4 million people in the country. The population then more than doubled by 1900 (to 76.2 million), added another 100 million by 1960 (to 179.3 million), and by the 2010 census there were 308.7 million people living in the United States, making it the world's third largest country after China and India. Assuming a constant rate of immigration, the United States will have nearly 400 million people by 2050 (see figure 1).

(Figure 1 here)

American population growth has outpaced that of most other peer countries. Figure 2 compares American population growth with that of many large countries in Europe over the nearly two-hundred-year period from 1820 to 2012. All countries grew, with even the slowest-growing country of those shown-France-doubling its population. American growth, however, was much more dramatic: it grew by over 3,000 percent. The world's total population also grew rapidly over the period, from 1.04 billion to 7.06 billion, but this increase (578 percent) was still well below that of the United States. The largest countries today-China (1.35 billion) and India (1.26 billion)-were already relatively large in 1820 (381 million and 209 million, respectively), so their growth rates were also smaller than the U.S. one.

(Figure 2 here)

The size and composition of a country's population are determined by the interplay of three forces: fertility, mortality, and migration. Rates of all three have changed considerably through the course of American history. Many of the changes in the United States reflect those that have occurred in all developed countries, and they collectively represent its demographic transition. According to demographic transition theory, societies typically experience a change from a regime of high fertility and high mortality to one of low fertility and low mortality. During the pretransition stage, population growth is slow because of the balance between high fertility and mortality. Couples typically have many children to ensure that at least some of them will survive to adulthood. The first stage of the demographic transition involves a decline in mortality. The decline is caused by advances in public health and medicine. As mortality declines, a population's growth rate increases. In the next stage, fertility begins to fall; this occurs after the decline in mortality, because social customs, traditions, and habits centered on having many children are often slow to change. Eventually, according to demographic transition theory, low mortality is matched by low fertility, and population growth once again stabilizes. All developed countries, and indeed most countries around globe, now have relatively low levels of mortality and fertility. Fertility rates, however, are still quite high (though declining) mainly in a number of African countries today.

These days many developed countries have what is termed below replacement fertility-fertility rates that are so low that if they do not increase, the country (in the absence of immigration) will eventually face a decline in its population. For populations to remain stable, women have to have on average just over two children (essentially to replace the mother and father and to allow for some infant mortality). Fertility rates in Europe and East Asia are currently well below replacement level, as their total fertility rates (TFRs, which refer to the average number of children per woman over her lifetime) are close to 1.5. Mortality is quite low in these countries, women (and couples) are choosing to have small families, and often they invest heavily in the children they do have. Fertility in the United States today is also low, but high relative to fertility in many of these other countries; in 2012 the U.S. TFR was 1.9. The U.S. population will likely continue to grow at a significant pace for many years to come because of persistent immigration as well. I now offer a more detailed look at historical patterns of mortality, fertility, and migration in the United States.

U.S. Mortality

In 1789 life expectancy at birth was only about 35 years in the United States. Mortality remained fairly stable and perhaps even increased in the first few decades of the nineteenth century as a result of greater urbanization, exposure to diseases, and poorer nutrition than at the beginning of the century. Not until 1870 did mortality begin to decline significantly. Life expectancy in turn began to increase rapidly-to about 49 years in 1900 and 64 years in 1940. Since then, life expectancy has continued to inch up, reaching 79 in 2010. One in five Americans born in 1900 died before reaching the age of 18. In contrast, only one in five Americans born in 2000 will die by the time they reach 75, according to recent estimates. Advances in life expectancies in the late nineteenth century through the early twentieth were most affected by declines in infant and child mortality, though mortality declined across the entire age spectrum. Declines in mortality among children were achieved mainly by progress in controlling the spread of infectious diseases. In contrast, increases in life expectancy in recent decades have been driven more by extending life among the elderly, especially those who are very old.

Table 1 shows the leading causes of death in the United States in 1860, 1900, and 2012. In 1860, the leading causes of death were overwhelmingly infectious diseases such as tuberculosis and cholera (ranked first and third) and illnesses that infants and young children are particularly susceptible to, such as diarrhea (ranked second). By 1900, many of the same causes were still conspicuous, but we see a couple of prominent diseases that tend to occur later in life creep onto the list, including heart disease (ranked fourth) and cancer (ninth). By 2010, the list is dominated by causes of death that typically occur later in life, with heart disease and cancer topping the list-about 47 percent of all deaths were attributed to these two causes alone in that year.

(Table 1 here)

Declines in mortality in the nineteenth century were achieved by public health measures, including garbage and waste removal, the building of community water and sewage systems, the isolation and quarantining of infected individuals, and health behavior campaigns that advocated changes in individual and institutional hygienic practices, such as hand and food washing and the boiling of milk. These practices helped reduce mortality in many relatively rich countries, such as England, Sweden, and France, at approximately the same time within about a 20-year period in the late 1800s.

Cholera, for example, killed tens of millions of people across the globe in the nineteenth century and about 150,000 Americans in one pandemic alone from 1827 to 1835. Conventional wisdom of the time had it that cholera was caused by "miasma"-a form of "bad air"; this was the time before the germ theory of disease had been developed. Eventually, the cause of cholera and other infectious diseases became better understood. The physician John Snow, for example, tracked down the source of the 1854 cholera outbreak in London by talking to local residents of the Soho neighborhood. He found a cluster of cholera cases right around a public water pump on Broad Street. People later discovered that the water pump had been dug only three feet from an old sewage pit that had leaked fecal bacteria. Knowledge about the sources of disease eventually led to effective public action. The first water filtration was introduced in the United States in 1872 (in Poughkeepsie, New York), though the largest cities did not build filtration plants until the early 1900s. Chlorine treatment of water also became the norm during this period, and the pasteurization of milk and other dairy products became standard practice everywhere. The last decades of the nineteenth century also saw the development of a number of vaccines for rabies, typhoid, cholera, diphtheria, and the plague.

While public health measures and sanitation practices were the most important triggers of the decline in mortality through the early twentieth century, nutritional improvements also allowed people to avoid contracting disease and better withstand it once it was contracted. Even with the decline in mortality from infectious diseases, such illnesses were still prominent causes of death through the middle of the twentieth century. During 1918 through 1920, for example, somewhere between 50 and 130 million people died during a global flu pandemic, including about 500,000 to 675,000 in the United States. The high death toll was caused by both a very high infection rate and the severity of the symptoms.

The continued decline in infectious diseases in the middle decades of the twentieth century was driven by the growing importance of medical care in the form of the widespread diffusion of medicines, including sulfa drugs and penicillin. These drugs were used extensively in treating pneumonia but were used for other diseases as well. Pneumonia and flu deaths declined at an annual rate of 3.9 percent per year between 1940 and 1960, faster than the 2.4 percent annual decline over the forty years previous. This eventually led to the more recent mortality regime in which chronic and degenerative diseases mentioned above are the leading causes of death rather than infectious ones.

While the decline in mortality and the lengthening of life expectancy played some role in the growth in the U.S. population over the past two hundred years, other factors were also clearly at work. After all, most European countries depicted in figure 2 experienced the same kind of mortality transition and increasing life expectancy that the United States did over a similar period of time but did not grow as quickly as the United States. Does fertility, then, explain exceptional U.S. growth rates?

U.S. Fertility

The United States initially had very high fertility rates. In 1800, the total fertility rate was 7.0, indicating that women were having, on average about seven children in their lifetime. This figure might have been even higher in the preceding decades, though the data for this period are sparse. Writing in 1798, Thomas Malthus believed that the growth rate of the American colonies was "probably without parallel in history." Benjamin Franklin also weighed in on rapid U.S. population growth fueled by high fertility:

Land being thus plenty in America, and so cheap as that a laboring man that understands husbandry can, in a short time, save money enough to purchase a piece of new land sufficient for a plantation, wheron he may subsist a family; such are not afraid to marry. . . . Hence marriages in America are more general, and more generally early, than in Europe. And if it is reckoned there that there is but one marriage per annum among 100 persons, perhaps we may here reckon two; and if in Europe they have but four births to a Marriage (many of their marriages being late), we may here reckon eight, of which if one half grow up, and our Marriages are made, reckoning one with another twenty years of age, our people must at lest be doubled every twenty years.

U.S. fertility was thus very high by the standards of the European countries from which much of the U.S. population had emigrated. England and France, for example, had total fertility rates closer to 5. As also recognized by Franklin, U.S. fertility rates were also much higher than the country's death rates, such that the population was on pace to double every 20 to 25 years from natural increase alone. It has thus been estimated that about three-quarters of the growth in the U.S. population from the founding of the nation until the Civil War was due to natural increase (an excess of births over deaths), with the remaining quarter due to immigration. While there is some debate on the exact timing of the beginning of the fertility decline in the United States, it is clear that fertility rates fell substantially in the nineteenth century to 3.6 in 1900. By the late 1800s the U.S. fertility rate matched those of western European countries, where fertility declines were only just beginning. U.S. fertility continued its descent to the near replacement level of 2.2 in 1940 (see figure 3).

(Figure 3 here)

The post-World War II period saw a remarkable spike in fertility, popularly known as the baby boom, which peaked with a TFR of 3.8 in 1957-a level not seen in the United States since the late 1890s. Thereafter, fertility resumed its decline, though it has been nearly stable in the vicinity of 1.8 to 2.1 since 1980. It is important to note that these TFRs represent averages, and variability has always occurred among the experiences of women and couples. For example, while women were having on average 3.6 children in 1900, about 20 percent of them had 7 or more children and another 20 percent had 1 or none at all.

The U.S. pattern of fertility decline does not altogether conform to demographic transition theory. Specifically, fertility began falling in the 1800s even before the onset of widespread mortality declines. In nearly all major western European nations (except France), birth rates remained stable for most of the nineteenth century and began declining only after significant mortality declines. Some speculate that fertility fell before mortality in the United States because fertility was so high in the first place and mortality was moderate-yielding very high rates of natural increase. Thus, the early decline in American fertility may mainly reflect the country's distinctive starting conditions involving very high fertility rates.

Many other social changes also accompanied fertility declines and thus may have played a role in reducing it. First, the United States transformed from a rural and agricultural society to a more urban and industrial one. In 1800 more than 90 percent of the population lived in rural areas, and 80 percent were engaged in agriculture. By 1900, the proportion of the population living in rural areas had declined to 60 percent, and there were corresponding declines in agricultural work. Land became scarcer as the century progressed. Families in rural areas were more likely to want to have many children to lend a hand on the family farm; in contrast, children were more expensive to raise in urban areas, where food had to be bought rather than produced.

Second, technological change and rising incomes may have served to reduce fertility. Technological progress spurred greater demand for an educated workforce. This led more families to invest in their children's schooling and education and thus increased the cost of raising children. Technological change also increased household incomes and the range of consumer goods available, which may have offered new alternatives for spending family income in ways other than rearing children and created new possibilities for upward social mobility. Third, the changing role of women in society made it increasingly possible and desirable for women to work outside the home. There was a growth in the number of white-collar (nonmanual labor) jobs, which were seen as more suitable for women. Over time gender equality increased, which made careers outside the home more socially permissible. A combination of all of these factors resulted in a new cultural norm of having a relatively small family.

The baby boom, which began in 1946, peaked in 1957, and lasted until about 1964, represents an aberration in the long-term downward trend in fertility. Fertility spiked for a number of reasons, including the end of the Great Depression and World War II and the booming postwar economy. The baby boom also occurred, to a smaller degree, in a number of other Western countries. The Depression and the war had served to depress fertility. Thus, when men came home from the war with ample opportunities to make a family wage (facilitated in the United States by the GI Bill) and many women left the labor market, couples who may have deferred having children decided that the time was right for them. This was also a time of suburbanization, which translated into larger homes and more space for metropolitan families. Improved nutrition, medical advances that reduced infertility, and cultural practices that led Americans to marry younger and have children sooner also played a role. The baby boom, however, was followed by a "baby bust," which lasted until the mid- to late 1970s. During this period fertility dropped precipitously (from 3.8 in 1957 to 1.7 in 1976), likely reflecting changing gender norms (e.g., more women in the labor market) and the increased availability of contraception and abortion, which allowed women and couples to regulate their fertility more effectively.

Overall, high fertility in the United States, especially from its founding to the last decades of the nineteenth century, played an important role in the country's rapid growth during that time. However, there was an additional reason for America's demographic rise: immigration.

U.S. Immigration

The first migrants to North America traveled in small bands from the Siberian plains across the Bering Straits into Alaska from about 30,000 to 40,000 years ago. Many moved south and eventually spread throughout the Americas. In more modern times, starting with the settlement at Jamestown, Virginia, in 1607, roughly four waves of immigration to the United States have occurred. The first wave lasted until about 1820. From 1607 to the adoption of the Constitution in 1789, close to a million people came to the United States-about 600,000 from Europe and 300,000 African slaves. A solid majority of the total U.S. population at the time of the first U.S. census, in 1790, was from England (60 percent), but many settlers also came from Scotland, Germany, the Netherlands, and France. These European immigrants came to the colonies for a variety of religious, economic, and political reasons, such as economic opportunity or the desire for freedom from religious persecution in their home country. Thus, even at this time the United States was very ethnically and religiously diverse, especially compared with the societies from which the immigrants came. As indicated above, the large number of involuntary black migrants who were victims of the slave trade also contributed to the growth of the U.S. population. These slaves were overwhelmingly concentrated in southern states: slaves constituted a full third of the population of the states south of Delaware. The arrival of the European settlers also had the effect of drastically reducing the Native American population through warfare and especially the spread of unfamiliar diseases to which they had no immunity.

The second wave of immigration spanned the period between 1820 and 1860. This wave included farmers, laborers, and artisans displaced by the Industrial Revolution in Europe. The primary countries of origin during this wave included Germany, England, and Ireland. Unlike in the first wave, Roman Catholics predominated in the second. This caused great apprehension among certain segments of the native U.S. population. Anti-Catholic sentiment occasionally turned violent, such as in the destruction of Catholic churches in the 1850s in places including Sidney, Ohio, and Dorchester, Massachusetts. Politically, the anti-immigration forces came together to form the American Party (also known as the Know-Nothing Party) of the 1840s and early 1850s, which called for the stiffening of naturalization laws. These efforts were generally unsuccessful.

The third wave of immigration occurred roughly between 1880 and 1914. During this period, over 20 million southern and eastern Europeans arrived, as well as several hundred thousand Chinese, Japanese, and other Asians. By 1910, about 15 percent of the U.S. population was foreign born. In 1882, 87 percent of immigrants were from northern and western Europe and 13 percent from southern and eastern Europe, but by 1907 only 19 percent arrived from northern and western Europe and 81 percent came from the southern and eastern portions of the continent. This wave of immigrants was again met with considerable alarm by nativists, but this time their efforts were more successful than previous attempts to restrict immigration. First, the Immigration Act of 1882 prohibited immigration from China. This act, rooted in racial prejudice, was passed in response to complaints from workers in California who opposed "unfair competition" from Chinese immigrants. Immigration from Japan was also later restricted in 1907.

Antipathy toward immigrants extended to those from southern and eastern Europe, who were often considered to be genetically inferior and unassimilable. A 1907 U.S. House of Representatives commission study concluded that immigrants from these regions had more "inborn socially inadequate qualities than northwestern Europeans." This eventually led to broad quantitative restrictions on immigration passed by Congress in the form of the Immigration Act of 1921, followed by the more stringent Immigration Act of 1924. These acts, along with two world wars and a depression, led to a lull in immigration from 1915 to the end of World War II.

After World War II immigration policy generally became less restrictive. Many government officials and commentators felt that for the United States to be perceived as a beacon of freedom and democracy-in contrast to its Cold War rival, the Soviet Union-it needed to revise its overtly discriminatory policies. An increasing proportion of the public came around to the idea that racial oppression was antithetical to the Enlightenment principles on which the country was founded. They felt that such oppression was hypocrisy, to put it plainly, and a blot on the nation's character and international reputation. Immigration began creeping upward during this period (from the late 1940s to the early 1960s), with a rising tide of Mexican immigrants admitted via the Bracero Program-a temporary worker program designed to fill labor shortages in agriculture.

The fourth wave of immigration has occurred from 1965 to the present. In 1965 Congress passed the amendments to the Immigration and Nationality Act (also known as the Hart-Celler Act), which fundamentally revised immigration policy. This act eliminated the discriminatory national quota system, which favored northern and western Europeans, and opened up immigration to areas outside Europe and the Americas. This opening of immigration policy resulted in a spike in immigration, especially from Asia.

Figure 4 illustrates these long-term trends in immigration. The sharp peak in the number of legal immigrants in the late 1980s and early 1990s mainly reflects the passage of the Immigration Reform and Control Act (IRCA) in 1986, which had provisions that allowed previously undocumented immigrants already in the United States to receive legal status. The real peak of immigration occurred before World War I (the peak year was 1907, with the arrival of 1,285,349 legal immigrants), and then the country experienced a rapid decline after the restrictive policies in the 1920s. The all-time low was registered in 1933, when only 23,068 immigrants arrived and when the U.S. unemployment rate hit a high of 25 percent during the Great Depression. The figure also indicates that the growing number of immigrants after World War II eventually matched the numbers from the early twentieth century. Through most of the 2000s, over 1 million legal immigrants have arrived annually.

(Figure 4 here)

However, because the overall population of the United States has continued to grow, the proportion of its foreign-born population today does not quite match that segment's historical highs (see figure 5). In both 1890 and 1910 nearly 15 percent of the U.S. population was foreign born. This reached a low of only 4.7 percent in 1970-a time when many of the immigrants from the previous wave were dying and the post-1965 growth in immigration was just gaining steam. The baby boomers essentially came of age during a time when the percentage of the U.S. population that was foreign born was at an all-time historical low. By 2010, however, nearly 13 percent of the U.S. population was foreign born.

(Figure 5 here)

As indicated earlier, through most of the nineteenth century a majority of immigrants came from northern and western Europe, with the three largest sending countries being Germany, Ireland, and the United Kingdom. The late 1800s saw a large increase in the proportion of immigrants coming from southern and eastern Europe; between 1900 and 1909, 42 percent of immigrants came from Russia and Italy alone. Immigration from Mexico slowly accelerated after World War II, and the rapid increase in the percentage of immigrants from Asia began in the 1960s. The 2000s have also seen an appreciable number of immigrants from Africa (7 percent of all immigrants). As a consequence, the proportion of all legal immigrants in the United States who were from Europe was only 13 percent from 2000 to 2009, down from 86 percent in the 1900-1920 period. The share of all immigrants from Asia grew from 4 percent to 34 percent and from Latin America from 10 percent to 41 percent over the same time period. Immigration from Asia has accelerated in recent years and in fact has surpassed the number of Hispanic immigrants since 2009.

Internal Migration

High levels of immigration were accompanied by high levels of internal migration through U.S. history. Two long-term processes characterize this internal movement: the westward expansion of the population and its movement from rural areas to urban ones. With regard to westward expansion, at the time of the first census in 1790 only 13 percent of the total population lived in territories west of the thirteen original states, which of course were situated on the eastern seaboard of the United States, where the first European colonists had settled. By 1860, however, a full 55 percent of the population was living west of these states. The framers of the Constitution had made it easy for new territories to gain statehood, and by the eve of the Civil War in 1860 there were thirty-four states in the Union. Americans were also considered more mobile than their European counterparts. As remarked by an English observer, Americans "acquire no attachment to Place. . . . Wandering about Seems engrafted in their Nature; and it is a weakness incident to it, that they should forever imagine that the Lands further off, are still better than those on which they have already Settled."

The westward movement of the population is illustrated in figure 6. It shows how in 1790, the center of the population was east of Baltimore, Maryland. By 1860 it was in southern Ohio, by 1950 it was in Illinois, and by the time of the 2010 census the center of the U.S. population was in Missouri, well southwest of St. Louis. The map also shows the more recent southern movement of the population since about 1950. This represents the rise of the Sun Belt, or the southern migration of the U.S. population away from the Northeast and Midwest to the South and West, to states such as Texas, California, Nevada, New Mexico, and Florida. Also illustrating this pattern of mobility, over a quarter (27 percent) of the native-born population lived outside their state of birth in 2010; this is in line with historical patterns, in which 22 to 31 percent of the population lived outside their state of birth at different points in time.

(Figure 6 here)

The second pattern of internal migration was the movement of people from rural areas to urban centers. In 1790 only six towns in the United States had more than 8,000 people, with New York City the largest with 33,000 people and Philadelphia the second largest with 29,000 people. Only 3 percent of the U.S. population lived in these six towns at the time. However, cities grew at a faster rate than rural areas in subsequent decades as they became centers of bustling trade. The proportion of the U.S. population living in all urban areas grew from just 5 percent in 1790 to a 26 percent in 1870, 51 percent in 1920, 75 percent in 1990, and 81 percent in the latest 2010 decennial census (see figure 7). The rapid growth of cities in the late 1800s and through the 1900s was fueled by industrialization, for example, the steel factories in Pittsburgh, the textile industry in New York, meatpacking plants in Chicago, and the explosive growth of the automobile industry in Detroit.

(Figure 7 here)

Industrialization and urbanization are reflected in the growth rates of individual cities. In 1860, New York had 814,000 inhabitants, followed by Philadelphia with 566,000. Just forty years later in 1900, New York City had grown to 3.4 million people, Chicago had 1.7 million, and Philadelphia 1.3 million. Immigrants swelled the populations of these cities. New York itself was a major port of entry at the turn of the twentieth century and was largely divided into ethnic neighborhoods. Jacob Riis, in his classic book on poverty, How the Other Half Lives, describes the often-desperate conditions in which poor immigrants lived, crowded as they were in dense, poorly constructed tenement housing. As Riis writes,

A map of the city, colored to designate nationalities, would show more stripes than on the skin of a zebra, and more colors than any rainbow. The city on such a map would fall into two great halves, green for the Irish prevailing in the West Side tenement districts, and blue for the Germans on the East Side. But intermingled with these ground colors would be an odd variety of tints that would give the whole the appearance of an extraordinary quilt. From down in the Sixth Ward . . . the red of the Italian would be seen forcing its way northward along the line of Mulberry Street to the quarter of the French purple on Bleecker Street and South Fifth Avenue. . . . the Russian and Polish Jew, having overrun the district between Rivington and Division Streets, east of the Bowery, to the point of suffocation, is filling the tenements of the old Seventh Ward to the river front, and disputing with the Italian every foot of available space in the back alleys of Mulberry Street. The two races [Italians and Jews], differing hopelessly in much, have this in common: they carry their slums with them wherever they go, if allowed to do it.

But in tandem with the growth of these poor, racially distinct immigrant neighborhoods were the architectural marvels representative of the growing wealth and standards of living of the city: the modern skyscraper. New York and Chicago initially dueled to be the home of the tallest of these new buildings in the 1880s. New York took the lead for many years beginning in the 1890s and saw a sustained period of skyscraper construction between the 1910s and early 1930s, culminating with the erection of the Empire State Building, which was the world's tallest from 1931 until 1972. These cities continued to grow and thrive even with the relative lull in immigration in the middle decades of the twentieth century. They also saw a rapid growth in their black populations, fueled by a large-scale migration of blacks from the Jim Crow South to the North in search for jobs in bustling factories, in what became known as the Great Migration. By 2010, the largest three metropolitan areas in the U.S. 2010 census were New York (18.9 million people), Los Angeles (12.8 million), and Chicago (9.5 million).

As an aside, it should be noted that the world's tallest buildings today are in countries elsewhere in the world. These include the Burj Khalifa in the United Arab Emirates, the Makkah Royal Clock Tower Hotel in Saudi Arabia, Teipai 101 in Taipei, and the Shanghai World Financial Center in Shanghai. The One World Trade Center in New York City, completed in 2013, is in the top ten, and is the tallest building in the United States. The eclipse of American cities as the homes of the tallest buildings coincides with the urbanization and development of large industrial cities across the globe. As of 2011, the five largest urban agglomerations (cities and their surrounding commuting areas), as defined by the United Nations, included Tokyo, Japan (37.2 million); Delhi, India (22.7 million); Mexico City, Mexico (20.4 million); New York, U.S. (20.4 million according to the U.N. definition); and Shanghai, China (20.2 million). Close on their heels and rounding out the top ten are Sao Paulo, Brazil (19.9 million); Mumbai, India (19.7 million); Beijing, China (15.6 million); Dhaka, Bangladesh (15.4 million); and Kolkata, India (14.4 million). It is no surprise that a number of the largest cities in the world are in China and India-the two most populous countries, which are also experiencing rapid economic development.

Back to the development of U.S. cities: during the twentieth century we also saw a considerable redistribution of populations within urban centers. While only a quarter of the population of U.S. metropolitan areas resided in suburbs in 1910, by 1960 about half did, and by 2010 this figure was up to 61 percent. This suburbanization in the twentieth century was a result of several developments, including the rise of the automobile, which allowed residents to live farther from their central city jobs than they used to, the movement of jobs themselves to suburban locations, and the desire of many families to "escape the noise, dirt, crowding, and crime that city dwellers must tolerate."

Public policy also fostered suburbanization, such as through the provision of generous credit terms to home buyers, especially in the suburbs, after World War II and the Interstate Highway Act of 1955, which facilitated suburban commuting. While affluent and middle-class whites initially propelled suburbanization, and whites remain overrepresented in the suburbs today, minority suburbanization rates have increased rapidly in recent decades, and many immigrants today move directly to suburban ethnic communities rather than to traditional central city enclaves.

Conclusion

The United States has experienced profound social and demographic changes over the decades. Several demographic processes described in this chapter characterize the period from colonial settlement to today. The United States, like western European countries, experienced a demographic transition in the nineteenth and early twentieth centuries. This involved a change in a regime of high birth rates and high death rates to one of low birth rates and low death rates. However, U.S. population growth rates exceeded those of its peer countries. U.S. birth rates in colonial times through the early nineteenth century were particularly high, and its death rates comparatively moderate, yielding a very high rate of natural population growth. At its peak the U.S. population was doubling every 20 to 25 years from natural increase alone (i.e., not counting immigration). The 1800s saw a substantial decline in the U.S. fertility rate that continued through the middle decades of the twentieth century. These declines occurred by the end of the nineteenth century in other Western and developed countries and reflected social processes such as urbanization, growing levels of education and affluence, and growing gender equality-all of which tend to increase the cost of raising children. After a baby boom in the 1950s, fertility in the United States declined to what is now close to replacement levels-just under 2.0 children on average per woman.

As in a number of other western European countries, U.S. mortality remained moderately high before declining substantially in the last decades of the nineteenth century. This decline in mortality continues today. The initial reason for the decline was a better understanding of the transmission of infectious diseases, which led to effective public health measures and individual health practices, and later on, medical advances drove declines. The net result was a decline in infectious diseases, such as cholera, as the primary cause of death and the rise of chronic and degenerative diseases such as heart disease and cancer.

Immigration historically played a significant role not only in the country's growth but also in its composition. Through colonial times a majority of settlers came from England, though a substantial number of immigrants came from other countries such as France and Germany. Many slaves-involuntary immigrants-were also brought from Africa. During the early to mid-1800s a growing number of Catholic immigrants came to the United States, raising nativist concerns. These concerns were also later evident in response to the growing tide of immigrants from southern and eastern Europe (and China and Japan on the West Coast) in the last decades of the nineteenth century. This led to restrictions of immigration from the 1880s to the 1920s, and indeed the middle decades of the twentieth century saw a plunge in the number of immigrants coming to the United States. The latest wave of immigration occurred after changes in immigration laws in 1965 that overturned prejudicial immigration policies favoring immigration from northern and western Europe. Today, immigration flows are quite diverse, with significant numbers of immigrants coming from Latin America, Asia, and Africa.

Two long-term processes characterize internal migration: westward expansion, especially in the early days of the republic, and urbanization. The nineteenth century saw the continual addition of states as pioneers extended the frontier westward. The twentieth century saw additional population growth in western states, but after about 1950 we also see the rise of the Sun Belt, which included migration from the Northeast and Midwest to southern states.

Regarding the second process, urbanization, whereas only 5 percent of the U.S. population lived in urban areas in 1790, by 1900 this had risen to nearly 50 percent, and today over 80 percent of Americans live in urban areas. In addition, the population within metropolitan areas has become increasingly suburbanized. Whereas initially most residents in the suburbs were middle-class and affluent whites, suburbs today have become much more diverse, both ethnically and socioeconomically.

Fertility, mortality, and migration together thus explain the size and composition of the U.S. population. The growth of the country has in many ways been exceptional, driven initially by extraordinarily high fertility rates and continually by immigrants drawn to its affluence. The United States does not stand alone as a country of immigrants (Australia and Canada, for example, have been shaped by immigration as well), but it is one of relatively few with a long history of being a destination of immigrants from very diverse origins. This diversity has helped shape American political, cultural, and social institutions and helped propel the nation's continued economic growth.