The pirates do not yet realize that it may be cheaper for the Saudis to pay a few million to some people to attack the coastal villages and exterminate everybody there.
It would seem that if the people involved would simply clean out those pirate villages, pop them like a pimple, and then bulldoze the remnants into the ocean that this nonsense would come to a grinding halt. Negotiating with terrorists is poor strategy. You can only deal with them on terms that they understand. I would recommend to open negotiations with a few passes with an AC-130 gun ship. 6000 rpm with a small caliber mini gun would hose the scum off the decks and not damage the heavy steel structures.