Let me reiterate. Violence is not the answer for one reason and one reason only. Once it starts and everyone joins, it will be very, very hard to stop.
edit: be
The gunman made his own gun, in a country with ultra-strict gun laws. The Unabomber made his own bombs. The Seattle mall Islamist knife attacker refused to stay down after being shot multiple times.
My takeaway: political terrorists are particularly motivated. Secondly, gun laws slow them down but don't stop them.