reflecting on the immunity decision a bit, what the Court seems to be saying is that every element of the executive branch is at the President’s disposal, no matter what he wants to use it for. his motives don’t matter. the office is a weapon to be wielded however he sees fit.
I know this is tongue in cheek, but the point is that the limitation is the scope of the office as the Court sees it. within that scope, it’s open season. so under the majority’s logic, for example, there’s really no limit to what the president could use the military for.
