Friend was "fairly knowledgeable" -- just enough to know that a cocked gun can be a dangerous object. He wasn't knowledgeable enough to know what you know, which is that the 1911 is designed to be carried cocked & locked and is not inherently unsafe carried like that.And asks if I'd lower the hammer, because it makes him nervous (Whiskey Tango Foxtrot?)...
Sounds to me like a golden opportunity to teach your buddy something about the mechanics of guns.
Unless, of course, you don't know the mechanics of a 1911 well enough to quickly and easily explain them to an ignorant person (I'm not sure I do -- but then, I don't carry a 1911). If that's the case, I guess making funny faces about his comment would probably do the trick of making him back off, without revealing your own less than perfect knowledge.
(Heh, had a friend who was admiring my buddy's little single-action revolver. She commented that it seemed unsafe, since it took such a light trigger pull. I explained how it worked, and then showed her how the trigger didn't do anything at all unless the hammer was deliberately cocked. She instantly understood the point, and was greatly relieved. Definitely a victory for Our Side, as she's always been wary of guns and gun owners.)
pax
Everybody is ignorant, only on different subjects. --Will Rogers