Janice Shaw Crouse points out, “The crime of human trafficking is now the world’s second most prevalent crime (behind drug trafficking).”
There is an obvious difference between the two sorts of crimes: involuntary servitude inherently violates people’s rights, while drug distribution does not. How much more effectively could the world’s decent governments fight slavery if they redirected their anti-drug resources (involving consenting adults) to cases of human trafficking?
The government should do everything in its power to eradicate involuntary servitude (including all sexual exploitation of children) within its boundaries. The U.S. could also ease immigration rules for those vulnerable to the modern slave trade. Beyond that, private citizens should be glad to contribute to effective programs to fight slavery globally. (Readers who know of such efforts may leave a note in the comments.) Of course the best way to fight slavery is to promote capitalism, under which the rule of law triumphs and improved living standards enable the masses to thrive.