Was the latest round of airstrikes in Syria a one-time hit to restore deterrence and stop the future use of chemical weapons, or was it part of a slippery slope of more interventions in the Middle East?
President Trump was elected in part because he promised an end to optional wars, such as those in Afghanistan and Iraq, as well as the Libyan misadventure.
But Mr. Trump also guaranteed an end to perceived Obama-era appeasement. Mr. Trump said he would no longer put up with false red lines in Syria, or complacence about North Korea’s new generation of nuclear missiles.
He also claimed that he wanted to remind enemies that the penalties for attacking U.S. interests are not worth the risk of obtaining some sort of perceived transient advantage. And he inherited American overseas commitments symbolized by some 800 U.S. military facilities in 70 countries abroad.
These paradoxes were supposedly resolved by his administration’s doctrine of Jacksonian “don’t tread on me” punitive retaliation. Mr. Trump might promise to “bomb the s—t out of” the Islamic State, but then not send a division of U.S. Marines into Syria to police the savage postwar landscape.
This middle ground was more or less codified by former National Security Adviser H.R. McMaster in the recently published National Security Strategy. His team called threading the intervention needle “principled realism.” The Trump administration would use military force to protect U.S interests, but only in a context of what was practicable, given the existing quagmires abroad.