Gunboats in Elliott Bay

I was eating dinner at Elliott's Oyster House, when the waiter informed us that Dept of Homeland Security gunboats armed with two machine guns were escorting all ships back to the harbor. It seems to me that if someone was going to attack one of those boats, the attack would come from the inside of the boat, not the outside. Secondly, I would be more afraid of the gunboats than I would be of the terrorists if I were on one of those.