[mothered]

So long as you know many TOR exit nodes are monitored,

Provided the exit node remains In It's encrypted form and no Identifiable Information Is exposed, It'll be very difficult to trace a user back to It's original source by compromising all 3 servers (that Tor uses to route traffic- continually changing from one destination to another).

I'm not saying Tor Is fool-proof (nothing Is), but the degree of difficulty via Tor Is quite significant. Of course, MITM attacks and the like make the trace a lot easier.