President Trump ordered hundreds of active-duty uniformed military personnel from Fort Bragg, North Carolina, to Washington, D.C., on Monday to help restore "law and order" in the capital, and said if "a city or a state refuses to take the actions that are necessary to defend the life and property of their residents, then I will deploy the United States military and quickly solve the problem for them." Trump can deploy U.S. military forces in D.C., but elsewhere he either needs the consent of the governor or he has to invoke the Insurrection Act, a 1807 law that is rarely used in modern times.
"As scores of protesters made their way into Washington D.C.'s Chinatown district, a Blackhawk helicopter with U.S. Army markings descended to rooftop level, kicking up dirt, debris, and snapping trees that narrowly missed several people," The New York Times reports. "The maneuver, often conducted by low flying jets in combat zones to scare away insurgents, is known as a show of force." This "'show of force' snapped branches off trees and shattered some storefront windows," The Washington Post adds, citing local reporters.
Military helicopters hover over protesters in D.C. after ‘mandatory curfew’@Dacheslow