I don't think that the US could prevent a full-scale Russian or Chinese strike from causing massive damage. And I think that even the UK, France, and Israel could probably at least wipe out a couple of US cities.
Or at least more civilized than they would otherwise be. They make the US more civilized as well.
But I think my point stands - given that there are several countries that could destroy multiple US cities within minutes, the US does not have "a near-immunity to blowback, and a near-zero concern for consequences".