Globally, labor isn't scarce. If there were a true global labor pool, wages in USA would be further depressed.
People have no intrinsic right to immigrate into the country of their choice (they do have a right to leave their country if another will take them, however..)
An easy to understand introduction is to look at the Stolper Samuelson theorem.
This isn't a recent development. It precedes the existence of the United States as a nation. Textiles in the U.K., mill workers. It's been done before.
Protectionism is often just a straight subsidy from whichever society is being protectionist to the members which are being protected.
Or, as people on the Internet are prone to saying: if you can't compete, legislate. If you're somehow losing your job to Infosys, you can't be that good. Real loss for society occurs when a good candidate can't get into the US because Wipro took all the visas.
Anyway, my point was that protectionism and free trade have been fighting a war for centuries. It is not true that this won't be studied. It will and has been. Because it's nothing special and new. This is garden variety protectionism.
Blacks have no intrinsic right to move into the white neighborhood of their choice (they do have the right to leave their ghetto if another will take them, however..)