I'm from the area originally. That's a black bear, and black bears are far less aggressive than grizzlies. A griz has no fear of man.
Best thing you could have done if you were worried is to make a lot of noise and flail your arms around...he'd have run off.
As for packing heat in a national park - it's a felony. I wouldn't do it.
The wolves up there are the most dangerous killing machine. A pack of wolves is the most efficient hunting/killing machine in North America, and there's nothing they can't take down.
I've been up close to both grizzlies and black bears. It's unnerving to say the least. But it's important to know the difference between the two.
Also, to you guys who think a Dirty Harry gun is good bear medicine, you need to remember a couple things. First, a grizzly can sprint at 40mph. That means if he's 100 yards away, he can be all over you in about 3 seconds. Think you can squeeze off a lethal shot from a handgun on a moving target that quick? If you can, you're a better shot than most.
Second, handguns don't have the killing power of a rifle or a shotgun. A .44 mag puts a 300g round out at what....maybe 1300-1400 fps? Compare that to my 7mm Ultramag that can put a 175g round out at over 3000 fps. Unless that pistol round goes into the mouth or the nose, it's probably not going to be a lethal shot on a griz. The rifle will have much better penetration.
Studies show (and this is what we had when I worked for the USFS just outside of yellowstone for 7 years), that a deterrent is a better idea - yep, a big 'ol can of pepper spray. That'll buy you the time to get up a tree or get the heck out of there.
Next best is a shotgun loaded with 00 buckshot and with a wide open choke. At close range, that's about guaranteed to get some pellets in the nose - the most sensitive part of a griz.
Like I said, wolves are a lot more scary to me. Good luck getting 10 at once.