These observations, from Rosa Brooks at the Washington Post, may be relevant here. I've taken clips, since the Post remains a paywall site....
Trump’s bellicose rhetoric often precedes actions that are less draconian than his initial language would suggest, but this time, his threats may not be empty. Just look at the actions of federalized D.C. National Guard units operating alongside U.S. Park Police on Monday. These guard troops and their law enforcement colleagues weren’t quelling a riot or preventing a violent assault; instead, they were ordered to clear Lafayette Square so Trump could pose for a photo op in front of historic St. John’s Church. They did so with little restraint, and on Attorney General William P. Barr’s orders, using tear gas, flash grenades and rubber bullets to clear a path for the president and his Bible.
The same evening, a military helicopter with U.S. Army markings flew down to street level in the District’s Chinatown neighborhood, forcing frightened protesters to disperse. Meanwhile, reports suggest that units from the Army’s 82nd Airborne Division have already been activated and sent to the Washington area, along with units from the 10th Mountain Division and 1st Infantry Division....
No responsible citizens support looting or violence, regardless of the legitimacy of the underlying grievances — but deploying active-duty federal troops to American cities is still a stunning step. As former chairman of the Joint Chiefs of Staff Martin Dempsey tweeted after Trump’s announcement: “America is not a battleground. Our fellow citizens are not the enemy.”
Worse, Trump appears to be deploying combat units, not soldiers with expertise in law enforcement or nonviolent crowd control. Placing soldiers more used to Afghanistan, Syria and Iraq on American streets filled with angry, distraught protesters is an incendiary move — and one likely to end in tragedy...
It’s a situation fraught with terrible ironies. Most obviously, here in America, the “land of the free,” we’re well accustomed to condemning repression when we see it abroad. For instance, when the Polish government responded to the emerging Solidarity movement with violent crackdowns, President Ronald Reagan spoke out: The Polish government, he wrote, has “answered the stirrings of liberty with brute force. … How can they possibly justify using naked force to crush a people who ask for nothing more than the right to lead their own lives in freedom and dignity?” In 2015, when Burmese police used batons and fists against student protesters, President Barack Obama’s State Department issued a statement “condemn[ing] the use of force against peaceful protesters.”
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But there’s an even deeper and more painful irony. This isn’t the first time an American president has invoked the Insurrection Act over the strenuous objections of state and local officials — but the last time, the law was invoked to further the cause of racial justice, not hinder it.
In 1957, when nine black students attempted to enter an all-white school in Little Rock pursuant to a federal court order, then-Gov. Orville Faubus sent troops from the Arkansas National Guard to block them. With state troops under the command of a governor openly defying an order of the federal courts, writes legal historian William Banks, President Dwight D. Eisenhower scribbled his thoughts in a handwritten note: Standing by “in the face of organized or locally undeterred opposition by violence” would, he feared, cause “the entire court system [to] disintegrate” and lead to “the destruction of our form of gov’t.” Reluctantly, he invoked the Insurrection Act the next day, and soldiers from the Army’s 101st Airborne Division formed a protective cordon to allow the nine black students to walk safely to class...