Lets say, the 'bad' Super Mutants and the Nightkin try to have skirmishes with the NCR like how they did in that game that shall be known only as 3. Because it doesn't deserve the rest of the title. Would the NCR if they tried hard enough be able to exterminate the Super Mutants in New Vegas? I could see them launching an assault on Black Mountain, and the Brutes and Nightkins being the biggest threats.