They can easily claim this is a matter of national security at this point. You can bet that the registration of every truck in the area for the last 24 hours has been looked up and the Canadian intelligence apparatus has been set into motion investigating each of these people. They start sending RCMP around to their homes to question their families about their whereabouts and you will see a large majority disperse. The government is not willing, and quite frankly, can't let these people have a win.