I'm watching a documentary on Prince Harry's experience in Afghanistan on the BBC as part of the wedding coverage. Apparently he served on the front lines when possible and when his identity leaked out they tried to transfer him somewhere safer but he managed to get back to the front.
At any rate, supposedly a group of enemies dressed up as Americans and tried to infiltrate his base specifically in an attempt to kill Harry. IOTL they were discovered and repulsed. What would have happened had they actually succeeded?
Note supposedly William was training on flying for the RAF as well, though I doubt (as the heir) he'd see combat.