The Majority Report with Sam Seder just had a guest on today for an interview about this very topic. The guy’s name was Daniel Hunter and I found it solid.

The gist of the interview was that you can block boats that are carrying arms shipments with smaller boats and that might work for a while but the coast guard will probably fuck with you. So your best course of action is to get the dockworkers on your side and get them to not load the weapons onto the boats. I don’t know how much shipping is done in Utah as I’ve only been once.