The United States is a nation of immigrants. Except for a small number of Native Americans, everyone is originally from somewhere else, and even recent immigrants can rise to top economic and political roles.
But, despite this, more Americans are sceptical about immigration than are sympathetic to it. Opinion polls show either a plurality or a majority favouring less immigration. The recession has exacerbated such views.
Both the number of immigrants and their origin have caused concern. Demographers portray a country in 2050 in which non-Hispanic whites will be only a slim majority. Hispanics will comprise 25 per cent of the population, with African- and Asian-Americans making up 14 per cent and 8 per cent respectively. But mass communications and market forces produce powerful incentives to master the English language and accept a degree of assimilation.
While too rapid a rate of immigration can cause social problems, over the long term, immigration strengthens US power. It is estimated that at least 83 countries and territories currently have fertility rates that are below the level needed to keep their population constant. Whereas most developed countries will experience a shortage of people as the century progresses, America is one of the few that may avoid demographic decline.
For example, to maintain its current size, Japan would have to accept 350,000 newcomers annually for the next 50 years. In contrast, the US population is projected to grow by 49 per cent over the next four decades.
Today, the US is the world's third-most populous country; 50 years from now it is still likely to be third (after only China and India). This is highly relevant to economic power: whereas nearly all other developed countries will face a growing burden of providing for the older generation, immigration could help to attenuate the policy problem for the US.
In addition, though studies suggest that the short-term economic benefits of immigration are relatively small, and that unskilled workers may suffer from competition, skilled immigrants can be important to particular sectors - and to long-term growth.
Equally important are immigration's benefits for America's soft power. The fact that people want to come to the US enhances its appeal. Likewise, because the presence of many cultures creates avenues of connection with other countries, it helps to broaden Americans' attitudes and views of the world in an era of globalisation.
Singapore's former leader, Lee Kuan Yew, an astute observer of both the US and China, argues that China will not surpass the US as the leading power of the 21st century, precisely because the US attracts the best and brightest from the rest of the world and melds them into a diverse culture of creativity. China has a larger population to recruit from domestically, but, in Lee's view, its Sino-centric culture will make it less creative than the US.
That is a view Americans should take to heart. If Obama succeeds in enacting immigration reform in his second term, he will have gone a long way towards fulfilling his promise to maintain the strength of the US.
Joseph S. Nye is University Professor at Harvard. Copyright: Project Syndicate