Four Americans whose yacht was seized by Somali pirates were killed by their captors. David Goodman, over at the New York Times, notes that what happened "on the Quest appeared to mark a break from the usual behavior of Somali pirates, who tend to view harming hostages as bad for business."
My colleague here at the Naval War College, John Segerson, observes that this might be the equivalent of a 9/11 moment in how future ships react to Somali pirate attacks. The standard operating procedure during an airliner hijack prior to September 11 was to cooperate with the hijackers in the hopes of starting negotiations that would lead to the safe release of the passengers and crew; 9/11 changed that dynamic by showing that cooperation would lead to death and destruction. In much the same way, this incident might change the approach to dealing with piracy, in favor of strengthening resistance, for fear that pirates may end up killing their hostages.