A smarter, more open immigration policy can do much to create jobs and boost growth. The U.S. annually issues just 65,000 H-1B visas for highly skilled immigrants, with 20,000 more going to foreign professionals who graduate from a U.S. university with a master’s or doctoral degree. Yet in 2011, more than 150,000 students from China alone were studying in the U.S. Roughly 40 percent of international students receive U.S.-based grants or scholarships. In effect, the U.S. invests heavily in the education of foreigners -- most of whom are enrolled in the science-related fields that fuel high-wage employment -- and then prohibits them from pursuing job opportunities, allowing other nations to reap the benefits. (1)
The U.S. isn't the only place in the world to be happy, and increasingly there is little reason to be here. Probably a majority of skilled labor immigrants don't even want to stay here, they want to go home to be with their friends, family and culture. They only come for the schools and cache of an American university education.
If you are professionally educated in much of the developing world you can, if you want, have an entire fleet of servants, nannies, and attendants. You will live in place where everything is cheaper, you can save, and buy things with cash. Health care is cheap.
If you live in the U.S. you will have none of that, plus you're in an economy with almost no wage growth.
The inability to retain foreign talent has almost nothing to do with visa difficulties.
1'Help U.S. Economy With Visas for the Best and Brightest' - Bloomberg