Already there. The Oklahoma City bombing is only the most notable, but domestic terrorists coming from the military is growing. https://www.csis.org/analysis/military-police-and-rise-terro...
Honestly, you’re going to have bad apples no matter what. But what about the rest of the citizens? How can they respond to disaster scenarios without training?
Domestic terrorism is the same thing as abroad terrorism, except one uses patriotism as an ideology, the other uses religion.