akuperman, see the Insurrection Act:
The President, by using the militia or the armed forces, or both, or by any other means, shall take such measures as he considers necessary to suppress, in a State, any insurrection, domestic violence, unlawful combination, or conspiracy, if it—
(1) so hinders the execution of the laws of that State, and of the United States within the State, that any part or class of its people is deprived of a right, privilege, immunity, or protection named in the Constitution and secured by law, and the constituted authorities of that State are unable, fail, or refuse to protect that right, privilege, or immunity, or to give that protection.
The current riots are definitely “domestic violence”, so if the state’s authorities “are unable, fail, or refuse” to protect people’s rights the President has the full authority to do so, using the National Guard, the Army, or any other forces he has at his command.
In addition, Antifa and “Black Lives Matter” are unlawful combinations and conspiracies, and their involvement can easily be argued to make the riots an insurrection. But we don’t need to go there because domestic violence is sufficient.