Pirate ransom: counterparty risk in the endgame

The NY Times reports that Hijacked Arms Ship Limps Into Port (this is the Ukranian ship full of Russian tanks and other heavy weapons that I blogged about earlier).

An earlier report, Somali Pirates Said to Be Leaving Ship , sheds some light on the negotiations:
"Somali pirates freed a Ukrainian ship carrying tanks and other heavy weapons Thursday after receiving a $3.2 million ransom. The U.S. Navy watched the pirates go but didn't act because the pirates still hold almost 150 people from other crews hostage." ...
"U.S. seamen were inspecting the pirates' departing boats to make sure they weren't taking weapons from the Faina's cargo, Mikhail Voitenko, a spokesman for the ship's owners, said Thursday.
But the Navy was not taking action against the pirates because it did not want members of other crews still in captivity to be harmed, said Cmdr. Jane Campbell, a spokeswoman for the 5th Fleet in Bahrain.
''Even when you release Faina, there are still 147 mariners held hostage by armed pirates,'' Campbell told The Associated Press. ''We're concerned for their well-being.''"

This is the same U.S. Navy one of whose first missions was to fight the Barbary Pirates , an earlier African/Islamic manifestation of piracy. (Do you say a Navy won its wings? spurs? water wings?). So it is very plausible that the pirates worry that, when they release their last hostages, they will face military retaliation against their bases in Somalia.

This will make the endgame tricky.