We also see it in the United States, which faces the strains of an older population demanding expensive medical services from a slower-growing workforce. But the U.S. has a trump card that makes us different from Europe. Fareed Zakaria calls it our "secret weapon" in his book The Post-America World. It's immigration.



People want to move here, and we can take them. That's why, if you'll permit a bit of futurism, we're projected to have a lower share of seniors than most of the developed world by 2050.



Immigration is a big part of what distinguishes the U.S. from, say, the EU. Immigration makes us younger. That's what you see from the graph above. Immigration makes us smarter. Half of all Silicon Valley start ups have a co-founder no more than one generation separated from an immigrant. Immigration makes us work. The U.S. fertility rate is below 2.1, so it's immigration that pushes us above replacement level growth.

But don't gloat. There are cracks our armor.

One in three U.S. immigrants today was born in Mexico, making it the "biggest wave of immigration in history from a single country to the United States," according to the Pew Hispanic Center. But that wave hit a wall. Thanks to a weak U.S. economy, a growing Mexican economy, and a handful of other policies, net flow of Mexican immigrants to the U.S. has possibly reversed for the first time in several decades.

At the same time, "highly educated children of immigrants to the United States are uprooting themselves and moving to their ancestral countries," the New York Times reported just two weeks ago. The factors aren't all the same, but they rhyme. India is getting stronger relative to the United States, and, once again, public policy is getting in the way of immigration. We don't block foreign-born students at the Texas border. We kick them out if they can't marry, find a job, or snag one of a limited number of visas. In the race for human capital, this is a deliberate losing strategy.



There are reasonable arguments for using government laws and resources to limit immigration and protect jobs for American-born workers. But the broader picture is that the U.S. is failing to recognize a free and automatic virtue of being America: People want to move here and work in exchange for money.

More people working in exchange for money is what makes an economy go. Consider that in the 1990s, a remarkable 67% of the country (16 and over) was working or seeking work thanks to the Boomers entering their prime working years. But as those 80 million Boomers move into retirement, a smaller share of our population will be working, and a rising share will be seeking increasingly expensive medical attention.



A couple centuries ago, Thomas Malthus might have looked at stalling populations and cheered on behalf of limited wheat supply and other precious crops. Today we know better. The precious stuff that matters is people, especially smart people. That's the resource we need to replenish.

