Last night the Houston Rockets—with key players from Turkey, the Dominican Republic, and Argentina—defeated the Oklahama City Thunder, who rely on players from Switzerland and DR Congo in their rotation.
And in the NBA sector, we seem to have a clear example of a case where immigrants really do crowd out native-born American players. The total quantity of NBA players is essentially fixed (thanks to the owners' cartel) and the minimum salary for an NBA player is high (thanks to the Players' Association) so if you got rid of the foreigners and replaced them with guys who are currently in the D-League or playing in Europe, those guys would get raises. On the other hand, Serge Ibaka and Thabo Sefolosha would almost certainly suffer a pay cut. So why don't we kick those guys out? Well one reason might be that we think Ibaka and Sefolosha are not just foreigners, but also human beings whose interests count, and that imposing a "Serge Ibaka must move back to an impoverished country in Africa" rule would be a pretty mean thing to do.
Another reason, however, is that the category "users of immigrant labor" is not just the owners of the Rockets and the Thunder—it's the fans. Increasing the size of the talent pool from which the NBA can draw makes for higher-quality play and a more competitive league. The Miami Heat will probably win the championship this year. But if you remove Sefolosha and Ibaka and all the foreign-born San Antonio Spurs, then the Heat will definitely win and it'll be boring. NBA fans want the best possible product, and you get the best possible product by letting owners hire the right people for the job. That's not the capitalists pulling the wool over our eyes, it's a path to a more enjoyable world.
At the same time, it's obviously not the case that Aron Baynes' backup power forward job for the San Antonio Spurs represents him doing "jobs Americans won't do." Nor is it the case that it would be impossible for Spurs GM R.C. Buford and coach Greg Popovich to find a native-born American who's qualified to play backup power forward. You could probably write an article exposing the myth of the big man shortage and revealing that the real agenda here is to reduce wages.
But the really real agenda is to have a better NBA. And a better NBA is good for America not just because it's fun to watch, but because a successful pro basketball league is an American export product that we swap for oil and manufactured goods. Foreign basketball fans watch the NBA and buy NBA-licensed goods because it's the best basketball in the world, and we have an interest in keeping it that way. The presence of foreign players in the league also helps bring the foreign audience in. A fan of Pablo Prigioni from his time playing in Spain or Argentina might tune in to a Knicks game to watch him. Meanwhile, the existence of a foreign fan base for the NBA means that former NBA players can earn a wage premium if they drop out of the league and go to play abroad. Stephon Marbury was already a known quantity to Chinese fans when he went to China because NBA basketball is popular in China, and because Yao Ming's presence spurred interest.