In December of 1994, I was assigned to do a month's work on security clearances in Alaska, mostly for the National Park Service. One applicant was a historian who was going to be a law enforcement officer, so I had to interview a number of National Park Service historians who had worked with her. The head of the history department was a very petite woman with a PhD in History. She was very proud that she was certified as an expert marksman with the shotgun. All of the historians had to be shotgun-certified because they did a lot of field work and might encounter troubles with bears.
Sometimes, there are good reasons to carry firearms, even in national parks.
But the only weapon   I   ever carried in a national park was a black, government-issued ballpoint pen. Very effective weapon....

-Joe-