David,

High risk missions are just that, they're high risk, meaning there is a good possibility things will go wrong. UK SOF seems to adapt that reality more than risk adverse U.S. military leaders. As the SAS motto states, "who dares wins," but it doesn't mean you always win.

Regarding the St. Nazaire attack was conceived and planned by the SOE. They trained the commandos involved in the mission, designed the bomb and firing devise for the ship, and developed the deception plan to get the ship into the slot. Amazingly there was only one night of the year they could do this based on tides, full moon, etc. Unfortunately the deception plan backfired, the odd flying pattern of the UK bombers intended to make the Germans look left instead of right, actually heightened their alertness. This resulted the British destroy being detected and engaged before it reached it target. Several commandos were killed in the final assault to get the ship next to the target 4 minutes later than planned. They crashed into caisson, and then flooded the stern of ship so the Germans couldn't tow her away.

The saboteurs then attacked the pump house, which was essential for filling and emptying the dock of water. Without the pumps the dock was useless. That part of the mission was a success, but most of the commandos were now killed, wounded, or soon to be captured. There was great concern that the firing mechanism that was set to trigger the large bomb in the ship failed, but a couple hours after it was scheduled to blow it did so with enough force to create a tidal wave that generated additional damage. The dock remained inoperable for over a decade. Obviously the mission came at great cost to the commandos, but they achieved a strategic impact.

Of course, some will claim using a conventional ship packed with explosives to destroy a target isn't a true special operation, but I beg to differ. This mission depended upon unorthodox tactics, specially trained and equipped men willing to accept the risk, precise target intelligence, and so forth.