Arrests don't do any good unless the punishment is severe enough to attack the entire operation, including taking down their finances. Human trafficking is soooo more complex than you realize.
Yes it is complex. For example the auntie of a pretty 12 year old girl in an Ukrainian village tells her to go to America with a guy she knows for making good money and good life. Then the auntie collects her $1 reward. Many European countries, but not America tackle this right down to the source by letting the girl stay legal and remove her fear of being deported back. This way European law enforcement has data to take down such networks, that Americans will never imagine. Only America is stupid enough to need a war on prostitution.