Their innovations and entrepreneurship helped power the I.T. revolution that transformed the world. According to a study by the nonpartisan National Foundation for American Policy, more than half of the 91 start-ups that became $1 billion companies had one or more immigrant founders. Likewise, the Partnership for a New American Economy found that immigrants or their children had founded more than 40 percent of the 2010 Fortune 500 companies.
So what’s the cure for America’s dwindling demographic vitality?
A new baby boom generation would be enormously difficult to produce in a world with easy birth control. On average women say they want 2.5 children. But returning America to just a 2.1 replacement level through cash incentives would be “prohibitively costly,” as Lyman Stone of the American Enterprise Institute concluded after examining how these policies fared in European and other countries.
Instead, America might borrow a page from Canada. Its…