Just today, a man and his son were attacked by a black bear in Cades Cove in the Smokey Mountain National Forest. They were hiking on a remote trail, and were stalked by a young male bear. The son was attacked first, and the father beat the bear with sticks and rocks. The bear retreated, and disappeared, then made a second surprise attack.
The two were treated for puncture and laceration wounds, and then released at a near by hospital. This bear only weighed 55 lbs. and was killed by rangers when it acted aggressively towards them.
I say, let us be armed in the National Parks!