Re: "Two wrongs don't make a right." tl;dr.
"So, what's your solution to keep young women from being bought, abused and murdered ?"
I'd propose this:
10 Keep the site working under LEAs control for a certain period of time (a short period, a week or two at most).
20 Identify both sellers and buyers. There are tools that will identify a perv's IP and even pwn his devices.
30 If there is a suspicion that the life of one of the victims may be in immediate danger, rescue her or him immediately.
40 At the end of the intended period, do a massive sweep, save the victims and catch hundreds of criminals. Send them in for many decades/forever.
50 Keep the site working and you'll be able to catch even more criminals.
60 At the same time, many buyers and sellers that suspect the site is compromised will find a new website to do their business. Infiltrate and control said site. Or even create it yourself.
70 GOTO 10
I'd be very surprised if this method -that I didn't invent, as it has been used already in the Silk Road case- didn't produce a crop or two of hundreds of dangerous criminals every year.
Every criminal retired from the streets would probably save several victims in the near future. This is specially true for the sellers (or pimps) and the for craziest buyers.
I understand that with such an emotional issue, the "kill everything with fire" approach comes instinctively, but in this context it's not efficient at all for saving the victims and preventing more crimes.
Amongst other reasons, if you close all of these sites, the criminals will communicate by other means, as they did in the mythical times before the Internet. They'll go dark and the only way to identify and arrest the criminals will be through physically infiltrating their cells.
Another problem with making this kind of sites disappear is that said sites could operate from countries where American Laws don't apply (snark). Blocking the server's DNS would take the site down in the USA for a few hours, until the owners obtain a new DNS or proxy and distribute that new DNS using steganography or code words in some public forum or another.
A particularly nasty issue with this law is that it'd seem that nobody has bothered to precisely define the term "Sex Trafficking" ans include said definition in the law. Actually this part means that the law will be used and abused to put pressure on companies and individuals. As has been pointed out by fellow commentards, this would allow TPTB to have an absolute control over freedom of speech in the Internet.
If adult voluntary prostitution is included in the definition then all this law will do is harm the true victims, the prostitutes.
Thanks for you attention, sorry for this brick of a comment.