Thanks to Obama, no seriously, you are allowed to carry firearms in almost all national parks.
https://www.nps.gov/articles/firearms-in-national-parks.htm
https://www.nbcnews.com/id/wbna35484383
Got to see them live at Red Rocks in June. Pouring rain, 40 degrees and windy, and despite the weather it was one of the best live shows I've ever been to. They're an awesome band!