In a forum that isn't regulated by Nazis (had to get that in you know a discussion is over when Hitler or Nazis are invoked) or Marxists it is common for threads to wonder. It's a sign of freedom.
Yes my friend, by the grace of God we live in a place where free expression is a right, even if some might not like what is being expressed, for whatever reason. Some might argue that the Bill of Rights only limits what government can do, but I would say that it's also a blueprint for American cultural norms. I wouldn't call those who complain about what I post Nazi-like though, since there was no attempt to force anything on us; I'd say they were exercising the same rights we were exercising, and my response is to use those same rights to explain the flaw in their assertions. I did that, by explaining that what you and I were discussing was indeed related to bullet stopping power, and the part about the 9mm and PC bureaucrats especially was very directly related to the OP. I would add that a thread is never really derailed no matter what someone looking for an excuse to ***** about something might assert, since anyone who wants to is perfectly free at any time to post something that relates directly to the original. And no one is ever forced to read something they think is not pertinent or whatever. Letting a thread wander wherever it wants doesn't hurt anything IMHO.