The word "accountability" has a nice ring to it. Who can be against "accountability?"
I can. I am against "accountability" in any context where the likely overall cost of proposed actions to promote "accountability" outweigh the likely benefits. And so should every other rational person be.
Americans are very happy that the American captain was successfully freed, and grateful to the Americans who successfully freed him. The Americans had their orders, which they executed faithfully, cautiously, and patiently, which included instructions to fire if they believed the captain's life was in imminent danger; they made that determination, and based on the available information, I wouldn't second-guess that.
But this shouldn't blind us to the probability that every opportunity for a nonviolent resolution of the standoff was not exhausted by the Obama Administration. Judging from press accounts, President Obama made every reasonable effort to resolve the standoff without violence - subject to the constraint that the U.S. insisted that the pirates give themselves up to arrest and prosecution.
But that begs the question of why the U.S. should have insisted on this constraint. An alternative course would have been to trade freedom-for-freedom: freedom for the captain, freedom for the pirates.
Note that the cost of insisting that the pirates give themselves up for incarceration included a significant risk to the captain's life. Rescue operations, no matter how careful, skilled, or well-trained those carrying them out, do not always work. A recent French operation killed one of the captives.
This risk will now be even greater in any future standoff: any Somali pirate in such a situation in the future is going to be less likely to trust the U.S., and more likely to harm an American captive, and to minimize opportunities for safe rescue.