How much of it was being "forced" and how much was the decision that life as a stripper in the US was better than how they were living in Eastern Europe?
I would approve of our granting easy visas to cute Eastern European women with work skills.
Watch the movie “Eastern Promises” with Viggo Mortensen and
Naomi Watts. It is all about how Russian women are lured to come to the west with the promise of a better life.
The women are then kept in brothels where they are forced into prostitution and addicted to drugs like heroin.
http://www.imdb.com/title/tt0765443/
It is actually a very well done movie with a surprise ending.
They are enticed to come to the US under the auspices of real jobs and opportunity. When they get here they are usually told they owe a large sum for the transport and expected to pay for it. Through intimidation, physical abuse, sexual abuse, and drugs they are pushed into becoming sex slaves.
Sure they could walk away and check into a police station for help. However they are dealing with the Russian mob and know they will be found. Its an age old formula.