Proclaiming yourself a traitor and advocating sedition should be enough to start an investigation and lead to an indictment. Trials, jury, and sentencing...all the good due process is still owed to this person - if he is a citizen. If he is not a citizen, then he’s an enemy combatant without a uniform and gets no right to a trial at all.
Point being, you say you’re a traitor publicly and advocate for terrorists, you just put yourself on the no-fly list and got yourself an invitation to be questioned by the FBI.
WE NEED TO CRUSH WORTHLESS ISLAMIC MAGGOTS LIKE THIS WITH AN IRON FIST!!!
But first we get rid of our Leftist traitors.