You have to be careful about “slave labor” even on goods labeled “made in USA”. The Northern Marianas Islands have had some pretty bad sweatshop situations. That’s a US Territory and it products manufactured there can be labeled “made in the USA”. But employers there have held employees as indentured slaves while they work off their rent – even forcing abortions so that workers could stay productive. (google marianas sweatshop for more details.) This is a situation that elected officials from both parties kept hushed up.
Actually I just watched an episode of that Current TV program “Vanguard” about this very topic. I think the title was “The Battle of Saipan”. Indeed there was a lot of manufacturing in the Marianas throughout the 80s and 90s as US manufacturers tried to undercut the US textile workers with lower cost labor while still keeping a “Made in the USA” label. But now almost all of that work has been moved to China or Vietnam. Only one of the many factories on Saipan is still operating and it will apparently close soon. The people there are in bad shape, especially the immigrants from China and India that were sent there to work in the factories. Many of them can’t afford to return home. Just another day on the global slave plantation I guess.