Well, I think most of us agree that, usually, no dumbing down is required. Paramilitary forces might be used as goons, but they ain't the US Armed Forces. And if you do come up against the military, maybe you pissed them off, then you are probably fighting a team of unique super-normals. Sending the marines, or tanks, or jets are probably simply the wrong tools for the job.
Anyway, regardless of the method, if the entire US Government, or Armed Forces, wants you dead, then you'll probably get dead (well, unless you have a similarly large organization protecting you). The method is probably going to vary considerably, depending on the circumstances. I don't think many people here will argue that the US Government can easily kill a group of 4-10 people, even if they have super-powers (this doesn't include Cosmics, or such beastlies). And they will use the best tools available to do so, which probably won't be the army.