Yes you do if you want to change their labour laws.
You aren't changing the labour laws in their nations.
If firms want to trade with American firms, then they have to have certain work norms that they abide by in their contracts/.
America (or any country) can set whatever rules that it likes on firms that exist within its boundaries.
Those rules currently cover things like not taking bribes, not using sweatshop labour, not enabling terror groups - all which America is well within it's rights to set.
Those firms float contracts goes out, and international firms that can satisfy those rules, take them up.
If they don't want to, or cannot fulfill those contracts, they don't win the contract.