It's speculation to say how far Trump would go and how much of his bolster is just talk. Conceivably he could use or try to use the military to squash just about any demonstration. He threated to use the military to control the George Floyd protests. You may take this for what it's worth, which includes a discussion of the Insurrection Act and the powers of the president. There is a Crosby, Stills, and Nash song that comes to mind, something about Ohio?
"...Trump and his allies are making plans for how a second Trump administration would use the powers of the federal government to punish Trump’s critics and political opponents. Among other things, Trump would reportedly invoke the Insurrection Act—a law that gives the president nearly unchecked powers to use the military as a domestic police force—on his first day in office so that he could quash any public protests against him."
Trump wants to use the military against his enemies. Congress must act. (slate.com)