Only if you know exactly what you're doing, and never use an FBI-monitored exit node or visit an FBI-controlled honeypot site. Tor's threat model does not provide protection against an adversary that can monitor both the encrypted traffic coming from you, and the unencrypted traffic coming from an exit node or honeypot hidden service.

I don't understand why jimrandomh is claiming that Tor is "perfect". It certainly can be effective, but like most crypto, using it safely requires an adequate familiarity with its brittle points.