I remember reading a post quite some time ago from someone that had been in a gun fight. They said that rounds were fired from both sides. No one was hit. The guy said that he was going to get a more effective caliber. Someone left the response, "By more effective, do you mean a gun that you can actually hit somebody with?" That guy really hit the nail on the head. In my opinion, the smallest gun that you should carry is whatever caliber you are capable of keeping a good group at 15 yards. If you can't keep a 45 on target then don't carry one. If you are an awesome shot with a 22 then you are better off with that. I don't recommend a 22. But if that is what you need keep on target then carry it. I would rather put 10 rounds of 22 into a tight group. Then to miss eight times with my 1911. I do carry my 1911. But only because I am good with it.
Romans 1:16 I am not ashamed of the gospel, because it is the power of God for the salvation of everyone who believes: first for the Jew, then for the Gentile.