A sort of Trump doctrine grew in part out of Trump’s campaign promises and in part from the strategic assessment in 2016-17 by then national-security adviser H.R. McMaster, outlining a new “principled realism.” The net result is not to nation-build, preempt, or worry much about changing fetid countries to look like us, but to disproportionately respond when attacked or threatened, and in a manner that causes real damage, without the insertion of U.S. ground troops. We could call the Trump administration’s idea of deterrence without preemptive intervention as either “Live and let live” — or, more macabrely, “Live — and let die.”
