To protest domestic policy in foreign countries.: Pro Trade Restriction: We should not allow countries which violate human rights, deny democracy to its citizens, and so on, to benefit from gains from trade with our nation.; Con Trade Restriction: It isn't fair to punish the average citizen's consumption for the policies of her government.
To protest production methods in foreign countries.: Pro Trade Restriction: We should not trade with countries whose firms use child labor, whose workers are badly treated, or are virtual or actual slaves, etc.; Con Trade Restriction: The United States' history in these areas in not spotless, and by refusing to trade we only make that country poorer, making a bad situation worse.
To protest lax environmental concerns in foreign countries.: Pro Trade Restriction: By trading with countries who don't have or don't enforce environmental policy as vigorously as policy is enforced in the U.S., we are essentially exporting pollution, defeating U.S. environmental policy.; Con Trade Restriction: Strong environmental policy only arose in industrial nations after those nations were already wealthy. By trading with these countries we enable them to eventually earn enough wealth to be able to 'afford' environmental policy and to have the infrastructure to enforce it.