Attentat 1942: Obergruppenführer Reinhard Heydrich, governor of the Nazi-occupied Czech Republic, was attacked on May 27 1942 in a British operation. Two squads of Czechoslovak-exile commandos had been inserted into the occupied zone by parachute in late 1941, to link up with local resistance. Months of planning culminated in the partly-successful attack: though Heydrich survived initially, he later died of his injuries. Every one of the participants on the ground was uncovered and killed by the Germans. Civilian deaths due to prompt reprisals numbered in the thousands.

Upon learning of the nature of the mission, resistance leaders begged the Czechoslovak government-in-exile to call off the attack, saying that "An attempt against Heydrich's life.. would be of no use to the Allies and its consequences for our people would be immeasurable."
What did the assassination accomplish? Was it worth it, militarily or strategically? Was it ethically justified?

Hit and run thread -- I offer no further input.