The assassin did not act alone (minimally, he texted a roommate to pickup the murder weapon).
Now we need to:
-identify and roll up the whole Antifa network he belonged to.
-identify any university faculty or staff involved in Antifa, promoting the ideology, securing funding or space for meeting, etc.
-identify ties to foreign funding, influence, training, etc, which shouldn't be hard given Antifa is active in the EU and tied to LatAm and Russian Communist networks.
-Identify the stated purpose of Antifa as revolutionary overthrow of the government of the United States of America to which they apply violent, collective direct action.
-Name Antifa as an international terrorist organization and begin rolling up networks across the United States, and deploying military assets to handle their direction action.