The perpetrators should be tried quickly aboard whichever Navy vessel they find themselves on as of today. If the powers that be feel it is necessary, a military judge, prosecutor, and defense attorney can be dispatched to the fleet and hold a court martial. Otherwise, I'm pretty sure that the commanding officer of a warship in international waters can convene one with just as much legal weight as if it were held in Hampton Roads.
If found guilty of piracy, which to my understanding means "Was the accused on the ship without permission of her master and a party to her taking and/or the killing of her crew?", I suggest that all of the guilty be hung by the neck until dead within sight of their home port, with the event being broadcast live on CNN, Fox, SkyNews, and Al Jazeera. Any network that refuses to broadcast this warning to barbarians would lose its license to broadcast in the United States. All of the bottom feeding, cave dwelling, murderous cretins of the world need to know that after we count to 10 more than a few times, bad things happen to bad people.
After that, the president needs to man up and get congressional authorization for a punitive naval expedition against the pirates and their nests. My idea would be the immediate bombardment, not bombing, of the coastal villages that seem to breed this scum. A bombing would be too quick. I think the slow, systematic shelling of every standing structure in the port sends the right message. Nothing shows you care like having a cruiser park outside of RPG range and level the village.
RTWT at the link. Here's a guy who knows the score.