That we live in a time of unprecedented threats to the institutions of American democracy is obvious to anyone with access to media in 2025. It is even clearer to residents in two of the nation’s largest cities. In both Los Angeles and Washington, D.C., we have witnessed large-scale National Guard deployments in recent months, moves unrequested by local governors or mayors but authorized by President Trump in response to what he has called out-of-control crime and social chaos. Mr. Trump continues to float the idea of deploying the military in other major cities.

How did we get here? And is there a way back?

Using the National Guard for law enforcement is not just another instance of the overreach that has characterized every month of the second Trump administration. It is an even clearer break with one of the basic norms that safeguard our liberty: that American troops should not be patrolling American streets.

While reports from both cities suggest an emphasis on political theater—at this writing, in neither place have Guard troops found much to do—Mr. Trump’s rhetoric has been close to demagogic. His intention in sending the Guard into Los Angeles was to “liberate” the city from protesters against ICE raids, he said; in Washington, it was to prevent further “crime, bloodshed, bedlam and squalor.” 

In both cases, facts on the ground did not support his claims. Protests in Los Angeles had been largely peaceful and confined to a tiny area of the center city. Meanwhile, the Department of Justice reported in January of this year that Washington, D.C., has seen a 35 percent drop in violent crime since 2023. While its homicide rate is still higher than that of most major U.S. cities, the city is safer than it had been in over three decades.

But even if Mr. Trump had accurately described the degree of criminal activity in the capital, his use of the military to supercharge day-to-day domestic law enforcement would still be imprudent and alien to the best of the American political tradition.

In the Declaration of Independence’s long litany of complaints against the British crown, the misuse of the military is a repeated theme. King George III was accused of having “kept among us, in times of peace, Standing Armies without the Consent of our legislatures,” of “affect[ing] to render the Military independent of and superior to the Civil power,” and “Quartering large bodies of armed troops among us.” The signers of the Declaration realized that the regular presence of armed soldiers, answerable to their ultimate commander rather than to the people’s representatives, was incompatible with the self-governance of a free people.

While the second section of the Constitution makes the president the commander in chief of the armed forces, including the militia when called into actual national service, the first section assigns to Congress the power “to provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions.” Mr. Trump, in contrast, said in a cabinet meeting while speculating about sending the Guard into Chicago: “I have the right to do anything I want to do. I’m the president of the United States. If I think our country is in danger, and it is in danger in these cities, I can do it.”

As a constitutional federal republic, the United States usually relies in governance on a principle with roots in the Catholic tradition from Thomas Aquinas on, and clearly present today in Catholic social teaching: subsidiarity. As a governing principle, subsidiarity holds that competency and authority in governance or decision-making should generally devolve to the smallest unit whose concerns are tied up with that governance.

In the case of civil governance in the United States, this principle is most often seen in the historic tendency to privilege states’ rights over federal authority. Even the clearest example of federal authority superseding states’ rights—the Civil War—sparked much of our contemporary jurisprudence around the use of federal military force in local jurisdictions. 

Mr. Trump is not the first president to assert federal control of the National Guard over the objection of state leaders, and his administration argues that he is acting within the bounds of his legal authority and according to Congress’s delegation of power to him. Perhaps the most famous prior examples in American history of the use of the National Guard were the deployments commanded by Presidents Dwight Eisenhower, John F. Kennedy and Lyndon B. Johnson during the civil rights era. 

Few would argue today that such interventions were unjust. But those temporary actions, responding to the refusal of institutions to follow court orders to desegregate or to attacks on civil rights protesters, were clear responses to prevailing injustices. Segregation is not only bad policy, but, in the terms of Catholic moral theology, it relies on the constant violation of human dignity for the purposes of perpetuating injustice—a structural sin. 

Mr. Trump’s deployment of the Guard for general police duty lacks such moral clarity. The legality of the interventions in both Los Angeles and Washington is being challenged in the courts, but as the editors of America argued only last month, “Americans who are alarmed about assaults on democratic norms need to recognize that the courts alone are not a sufficient bulwark for the rule of law.” The most significant problem with these military deployments is not their questionable legality but that they are profoundly unwise, unlikely to achieve their nominal goals and dangerous to liberty. They should be resisted not only with lawsuits, not only by protesters demonstrating against them, but also by clear moral argument.

In the case of Mr. Trump’s interventions, the militarization of our cities is taking place without a clear justification—a casus belli, since these are indeed soldiers—other than rhetoric around crime and livability that seems aimed more at urban centers themselves rather than the protection of their residents. Soldiers may be able to offer humanitarian assistance after a national disaster; they may be able to force recalcitrant politicians to obey the law or a violent mob to disperse. But they cannot, over the long term, police a city into livability, and the attempt to have them do so is dangerous in itself.

Bring the troops home—even when home is just a day away. Allow our civil institutions that seek justice the room to do so without cribbing from authoritarian playbooks that Americans have rejected for 250 years. The president’s actions in Los Angeles and Washington, D.C., may have been mostly political theater—but that does not mean they are not a real threat to our American political tradition and to the common good.