While gains from trade usually generate increases in national incomes, they do produce winners and loosers. Most countries have government programs that are supposed to address this redistribution of income. In the US President Kennedy introduced the Trade Adjustment Assistance Program administered by the US department of labor.
The DOL's national statistics highlight that currently 280,000 US workers benefit from the program, at a cost of $575 million. That is about $2000 per worker - probably not enough to pay for retraining or any meaningful compensation for job losses. The state data is even more fascinating.