I've always heard of the expression "If you're going to carry a handgun for defense against brown bears, be sure to file the front sight off..."
Now it comes to light, or seems to anyway, that people are using .44 magnum, .357, 10mm, .45 auto, and even 9mm successfully as bear defense.
In the very event that I find myself in bear country, I suppose I'll be packing a handgun of some kind. But not a 9mm... (who was it who figured THAT out, anyway?) and no bear spray.
A powerful handguns is the better choice for grizzly/brown bears. But most black bear attacks are predatory in nature. In those, the bear often tries to figure out if the prey is dangerous, giving opportunities for an effective defense with even a .22 pistol.
I would recommend at least a 9mm, but any pistol is likely better than no pistol.
Here you go. Video shot from my boat on Baranof Island a couple of seasons ago.
I forgot to mention that in the little village in the video, Port Armstrong, we noticed that no one ever got more than arms reach from a 12 gage pump.