 FACT: Captain Pullman was wearing Silver Leaves on both sides of his  collar (not to mention 3 solid gold stripes on his shoulder boards),  which would mean that he actually is a Commander. However, the only  way that he would be addressed as "Captain" instead of "Commander"  is that hes in charge of all operations of the boat. The insignia  for a Captain in the US Navy (and Coast Guard) is identical to that  of a Colonel in the US Army/Air Force/Marine Corps.