The president is putting America’s armed forces in a bind

THE TECHNICAL term for it is a military-presence patrol. The non-technical term is a political stunt. Since August, National Guard troops have been ambling around landmarks in Washington, DC, including the Mall and the main train station. Donald Trump ostensibly sent them to fight crime. In reality they are not making arrests and these are some of the safer parts of America’s capital. So they are collecting rubbish and spreading mulch in city parks. Tourists ask them for selfies; some locals tell them to get lost. Soon Mr Trump will deploy more troops in Memphis and possibly New Orleans.

Thirty years ago Charles Dunlap, then an air-force lawyer, warned of the increasing encroachment of the armed forces into civilian life, which he called a “subtle drift towards an uncertain destination”. Under Mr Trump this is less a drift than a lurch. The president loves pageantry, hardware and men in uniform. He also thinks putting soldiers to work as cops in Democratic-run cities is good politics. Residents may resent it in DC and Los Angeles, where he sent troops in June to quell immigration-related protests. But it plays well on Fox News. A recent crime dip in DC validates his claim to have cleaned up that “dirty, crime-ridden death trap” (though this probably owes more to his surge of federal law-enforcement agents, who can make arrests). Republican governors in Louisiana and Tennessee want in.

Having endured British occupations of Boston, New York and Philadelphia during the American revolution, the founding fathers were deeply uneasy about having soldiers police civilians. Laws restricting such military deployments and presidents’ regard for tradition helped maintain that boundary. This suits the armed forces, who train to kill foreign combatants, not monitor fellow citizens. Mr Trump, in contrast, seems to have few reservations about using soldiers for political ends, be it dunking on Democratic mayors or carrying out his deportation agenda. In the process he is testing the boundaries of the law, the morale of the armed forces and a tradition of bipartisan support for that institution, one of the most trusted in America.

In LA and DC, soldiers have served mainly as a show of force. They are not arresting or searching people but are supporting police with protection and equipment. Their presence is a deterrent or, viewed more cynically, a prop. In California, troops did accompany Immigration and Customs Enforcement (ICE) agents on raids. Army lawyers have been seconded to work as immigration judges. The Pentagon has allowed ICE to use a navy base outside Chicago as a staging ground.

Co-operation of this sort will probably increase. Yet so far Mr Trump has avoided more fraught and potentially combustible moves. He has launched an immigration operation in Chicago but has not sent troops there. The presence of soldiers in LA is sparse, down from 5,000 in June, and they are staying put on an army base. He is deploying the National Guard to Republican states because those governors welcome it (even if Democratic mayors in the targeted cities do not). Still, it is worth imagining where more ambitious LA-type operations could lead: how, as in that city, raids could provoke protests which could turn violent, justifying the move to send in soldiers. If Mr Trump ratchets up his response, would the law constrain him?

Mr Trump’s deployment to LA was unusual in two respects: it was unnecessary and unwanted. The unrest that precipitated it was manageable. Protesters threw rocks and Molotov cocktails and set a car on fire. A federal agent broke a wrist. When past presidents sent in soldiers—to quell race riots, for example—they did so in the face of sustained, deadly violence and a near-total breakdown of law and order. Then overwhelmed governors sought federal help. Mr Trump acted over the objections of Gavin Newsom, California’s Democratic governor, who sued to block the deployment.

The laws that govern domestic use of the army are old, vague and open-ended. This gives the president a great deal of room for manoeuvre. He can send in troops to suppress a “rebellion” or enforce the laws if local authorities cannot manage. The Posse Comitatus Act (PCA), passed in 1878, bars soldiers from doing direct police work—hence the National Guard’s limited mandate in LA. But there is an exception if the president invokes the Insurrection Act. Scholars describe this as a “powder-keg” statute, empowering soldiers to search and detain people. Mr Trump has not gone there yet, though he reportedly mulled it in 2020 during Black Lives Matter protests. He backed off at the urging of his defence secretary and the chairman of the joint chiefs of staff.

A district-court judge said the California deployment was illegal; the ruling is on hold while Mr Trump appeals. The Trump administration is making two maximalist arguments: that the PCA does not apply in the case and that courts cannot second-guess its assessment about when a security threat justifies troops. It cites a 200-year-old Supreme Court ruling from the war of 1812, Martin v Mott. Then the court gave the president absolute discretion to call up a militia: “The authority to decide whether the exigency has arisen belongs exclusively to the President, and that his decision is conclusive upon all other persons.”

Should Mr Trump invoke the Insurrection Act, the Supreme Court will probably weigh in and may well cite that precedent. Ironically, the very success of the idea that soldiers should stay out of policing has created grey areas which empower a norm-busting president, notes Aziz Huq of the University of Chicago. Ordinarily vague laws get clarified when they are invoked and then litigated. That has not happened here because past presidents used them sparingly. Meanwhile, Mr Trump has first-mover advantage in his court fights.

A president can flex plenty of muscle without troops. Mr Trump has diverted 28,000 federal law-enforcement personnel—including one in five FBI agents—to do the work of ICE. And if a president’s goal is intimidation, police in camo, helmets and body armour can do that just as well. There was a telling moment during the recent trial in California. Pressed by lawyers, even federal officials could not tell who was a soldier and who was a law-enforcement agent. They looked indistinguishable: one big militarised blob. ■