From New Geography:
"To a remarkable extent, the United States has avoided these pressing demographic issues. The U.N. has the U.S. tied with Canada for the fastest projected population growth rate of any developed country: a 21% expansion by 2050. Yet this forecast could prove inaccurate.
One threat stems from millennials who, even with an improved economy, have not started families and had children at anything close to historical rates. Today the U.S. fertility rate has dropped to 1.9 from 2.0 before the Great Recession; population growth is now lower than at any time since the Depression. This places us below replacement level for the next generation. Projections for the next decade show a stagnant, and then falling number of high school graduates, something that should concern both employers and colleges. The United States’ high projected population growth rate, like that of Singapore, is entirely dependent upon maintaining high rates of immigration.
But even before the election of Donald Trump, who is hell-bent on cracking down on at least undocumented immigration, total immigration to the United States has been slowing. At the same time the fertility rates of some immigrant groups, notably Latinos, have been dropping rapidly and approaching those of other Americans. This is despite the fact that as many as 40% of women would like to have more children; they simply lack the adequate housing, economic wherewithal and spousal support to make it happen.
In the coming decades, the countries that can maintain an at least somewhat reasonable population growth rate, and enough younger people, will likely do best. To a large extent, it’s too late for that in much of Europe and East Asia. For countries like the United States, Canada and Australia, with among the most liberal immigration policies and large landmasses, the prospects may be far better. However, we also need native-born youngsters to launch, get married and start creating the next generation of Americans."