Donald Trump on Monday warned he would deploy the military in cities and states where authorities had not taken the “necessary” actions to quell violent protests triggered by the killing of George Floyd in police custody in Minneapolis last week.
The US president has argued a heavier military presence would have prevented violence and looting, blaming Democratic officials for not calling the National Guard out sooner.
“Mayors must get MUCH tougher or the Federal Government will step in and do what has to be done,” Mr Trump posted on Twitter at the weekend, saying he could deploy “unlimited power of our Military and many arrests”.
By nightfall on Monday, Mark Milley, chairman of the joint chiefs of staff, was patrolling the streets of Washington, DC, dressed in battle fatigues to the sounds of sirens and helicopters.
What are the rules governing the use of military force in America?
State governors can call out the National Guard if they need additional law enforcement. The National Guard, which emerged from the militia regiments of the 1630s that later defeated the British, is a military reserve force of 450,000 personnel. The majority of them are civilians contributing to the force on a part-time basis.
While some state deployments in the past few days are armed only with non-lethal force, some such as in Minnesota and Georgia have been allowed to carry lethal weapons.
The National Guard has sought to emphasise its pacific intent. “Guardsmen live in the communities they serve, and are there to protect their neighbor’s right to protest peacefully,” it said in a statement last weekend.
In the wake of protests over Floyd’s death, governors have activated more than 17,000 National Guard members in 23 states, across party lines, as well as in Washington, DC.
Mr Trump could decide to “federalise” the Guard and deploy its full-time military personnel across the country directly. However, an 1878 law named Posse Comitatus stipulates federal troops cannot be deployed to home soil to act against American citizens.
This means that while National Guard troops working under the authorities of a state governor have the right to support law enforcement, those working under federal order — known as “Title 10” — do not.
Can Trump use the Insurrection Act to deploy the military?
A law known as the 1807 Insurrection Act allows federal troops to be deployed to suppress lawlessness, insurrection and rebellion.
Invoking that act could allow Mr Trump to call out not only the National Guard but also the regular military — in most likelihood military police — and send them wherever he wanted. Mr Trump might be able to impose troops even if local and state authorities objected, citing protection of citizens’ rights.
However the legislation is “manifestly unconstitutional”, said Michael Brenner, professor of international affairs at the University of Pittsburgh, adding that it had never been tested in courts before, notably because governors had supported such deployments.
When was the US military deployed for domestic disturbances?
The Insurrection Act was last invoked in 1992 during the race riots in Los Angeles, after police officers were acquitted for beating Rodney King.
It was also used several times to defend civil rights in the 1950s and 1960s, including to enforce desegregation orders. It was also invoked to quell the 1968 race riots in the wake of the assassination of Martin Luther King Jr.
US Army troops guard the Capitol after riots broke out in Washington, DC, following the assassination of Martin Luther King Jr in 1968 © Bettmann/Getty
In 2005, then president George W Bush considered sending in the military to New Orleans in the wake of Hurricane Katrina but decided against it in the absence of actual insurrection.
“Historically the National Guard has not done terribly well in these kinds of situations,” said Mark Cancian, security expert at the Center for Strategic and International Studies, a bipartisan think-tank in Washington. “They tend to be heavily armed and the feeling of a military occupation makes people uncomfortable.”
In 1970, the Ohio National Guard shot dead four unarmed students who were protesting against the Vietnam war at Kent State University.
Is military intervention appropriate in this case?
Security experts are sceptical. Kori Schake, an expert in civil-military relations and director of foreign and defence policy studies at the American Enterprise Institute, a conservative think-tank in Washington, said it was “shameful” that General Milley wore battle dress to a White House meeting.
“It militarises what is not a military problem,” she said. It risks damaging the military’s relationship with broader civilian society, she added.
Peter Singer, a defence strategist, said defence secretary Mark Esper’s referring to the domestic US as a “battlespace” in a call on Monday with state governors was “wholly against his responsibilities to the American public and the Constitution”.
“It’s a terrible message to send to create this impression that we are now militarising domestic law enforcement,” said David Lapan, a former Pentagon spokesman who also worked under the Trump administration.
There was no need to invoke the Insurrection Act because states were already deploying National Guard, he noted. “The president is trying to portray himself as being more in charge than he actually is.”
The American Civil Liberties Union warned that deploying more federal troops would be “irresponsible and dangerous.”
“In general soldiers make lousy police officers,” said Mr Cancian, a former US Marine Corps reserve colonel. “Police officers are trained to look at civilians and see each one as a citizen with constitutional rights that must be respected. Soldiers are trained to see civilians as a potential threat.”
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