It certainly does. A cryptographic system that does not is useless. In the most basic sense, if you can't trust anyone you can't know if you're talking to a m

It certainly does. A cryptographic system that does not is useless. In the most basic sense, if you can't trust anyone you can't know if you're talking to a man-in-the-middle pretending to be someone else. TLS provides a mechanism for converting trust in a CA to trust that you're talking to the right party (who presented the certificate). If someone has a cert you accept and he's not the party you want to talk to that's not really TLS's fault and there's actually very little you can do about that. There are practical considerations as well but from a theoretical perspective it's secure.