In the post-World War II era, a handful of presidents have sent troops to quell violence sparked by desegregation or systemic racism. But before Trump, presidents deployed federal troops only to enforce federal court orders or support local officials who requested it. Before Trump, in moments of violence and division, presidents called for unity and respect. And before Trump, presidents viewed the decision to send in federal troops not as an opportunity to display force, but as a solemn duty to faithfully execute the laws of the United States.

Eisenhower, Kennedy, Johnson and George H.W. Bush seemed, for various reasons, keenly aware of the dangers of overplaying their hand. Eisenhower, after a distinguished military career, deplored the idea of sending a force trained for war to patrol a local school house. Kennedy wanted to secure a peaceful arrival to university for an American veteran, while negotiating with a governor who came from his own party. Johnson waited for Gov. Romney to use the right words, to make sure he did not overstep his constitutional authority. And Bush intervened only at the request of the governor of California and in the face of mounting evidence that law enforcement alternatives could not keep the people of Los Angeles safe.

Trump, by contrast, has adopted the language of battle. And he has not seemed at all concerned with fundamental constitutional notions of federalism and the rights reserved to states under the U.S. Constitution. Of course, Trump has not taken the final step of deploying the military to the states. But by deploying them cavalierly and in huge numbers in Washington, D.C.—without articulating what authorities he was using and over the objection of local officials—he showed that he is not particularly reticent about taking such a step. Trump’s approach, of course, is consistent with two central themes of his presidency. In moments of division, he peddles conspiracy theories and lashes out against his political opponents. And when it suits him, he pushes aggressively on the outer margins of his presidential authority with little regard for the precedent it sets.