I'm not disagreeing with you, but, if I'm not mistaken, American Samoa, while technically a US territory, is run by its own government.  I believe it's, on paper, under the authority of the Department of the Interior.  To say that this example constitutes the largest trafficking case in US history is, in my opinion, stretching the definition of the US a bit -- not that America isn't responsible to some extent.  (I'm sure we are.)

The balance of power between employer and employee certainly plays a role in those sorts of cases.  I don't disagree with you on that at all.  But the balance of power is not the be-all, end-all of human trafficking.  It's a symptom of a larger problem.  With the rise of China and India, clearly power has shifted to employers in the case of manufacturing, but that doesn't mean we can't support basic worker rights here.  Whenever there is a case of many workers being able to do a job, power is going to shift to the employer, just as power shifts to the employee when the employer needs him.

That's simple economics.  We can work to ensure that a shift in power doesn't translate to abuse of human rights by one party to the contract over another, but we can't stop shifts in economic power, because they result from forces that are generally outside of our control.

Be nice to America. Or we'll bring democracy to your country.