caz,
So how many people have they actually killed...?
A (very) quick google search revealed only one example of killing, when 4 hostages were killed when Special Forces stormed the yacht they were being held on....but I could well be wrong. I asked for some facts if anyone has them.
Kidnapping, false imprisonment, etc.... Yes, not nice crimes, and I'm not saying that Somali pirates are nice people - but do these acts warrant them being "shot on sight" in the same league as terrorists. In the case of terrorists you are often trying to kill the terrorist to prevent further loss of life (e.g. suicide bomber). Taking life in self defence during an act of piracy is different from a "shoot on sight" policy, especially when you consider that many of the countries involved don't have a death penalty for their own convicted murderers.
A robust international court system for bringing any pirates caught to justice would seem to me to be a necessity, and not just for the case of piracy on the high seas.