Insurrection Act of 1807. The President is allowed to use the military or whatever other means to suppress an insurrection if it

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

This may be the “after the election where optics are irrelevant” move, but it needs to be done at some point