Currently, the total fertility rate of the US is 2.09 children per female or just at replacement level. Add to that 1.1 million LEGAL immigrants a year and another 500,000 to 1 million illegal aliens annually and you arrive at an annual population growth of .89%, among the highest of all developed countries on earth.
Since 1970 we have added 100 million people and will add another 62 million in the next 23 years or the equivalent of the current population of the UK. By 2050, we will have a population of 420 million. One in four Americans will be Hispanic by 2050, which is quite a change from 1950 when Hispanics comprised 1% of the population.
Bureau of the Census Population Projections 2000-2050
Rome was underpopulated, relative to its empire; Spain at the time of its invasion by the Muslims was extremely underpopulated; and just about any place that has ever fallen has had a severe drop in population prior to its destruction.
The US is not going to experience any "severe drop in population" any time soon, i.e., during the 21st Century. Just the opposite. And the demographics of the country are changing rapidly with half of the children between the ages of 0-5 minorities. Demography is destiny. With the highest high school dropout rates being Hispanics and blacks and Hispanics having a birthrate is twice as high as that of the rest of the American population, there is reason for concern about the future.
Bush's America: Roach Motel by Ann Coulter
We need immigrants: we have to make them Americans, though, and that is where we are failing. And that’s our fault (permitting “bilingual ed,” separate language facilities for every group, special rights for Muslims, etc.).
Yes, we need immigrants. The question is how many and what criteria we use to bring them in. By 2050, non-Hispanic whites will be 50% of the population, down from the 89% in 1965 when the National Origins act of 1924 was replaced by Immigration and Nationality Act of 1965, a Ted Kennedy sponsored bill. The challenge will be to retain our national identity, language and culture with such an unprecedented mass migration of millions of immigrants, most of whom come from Latin America. Can we assimilate such numbers or will we become Balkanized along linguistic and cultural lines? Unless we change our legal immigration policies and eliminate extended chain migration, anchor babies, the visa lottery program, and go to a merit based system of immigration that serves the interests of this country, we will be finished as a nation.
The challenge will be to retain our national identity,
Something the Romans had difficulty doing.