So I'm anchored in the harbor on July 3, enjoying a nice picnic and swim with the Admiral and the crew when I notice that the Coast Guard is in the channel. They are slowly going up and down the channel, rafting up to some of the boats as they move in or out of the harbor. I can pick out a few words as they use their loudspeaker to hail the passing craft. At one point, I hear the Coasties say "We've got the blue light on....," and I notice that indeed, they have a flashing blue light (like a police light) going on top of the pilot house. Anybody know what that means? I assume they were out there on the holiday weekend to show the flag and provide security/terrorist deterrence. But I am curious if I am supposed to do something (avoid them, slow down, stop?) if I see the Blue Light on a Coast Guard vessel.