The year is 1943.
On the Kentish coast of England is a soldier -- let's call him Hilton, Private Clint Hilton -- manning an anti-aircraft gun. One day, Pvt. Hilton starts firing his AA gun at Allied bombers as they pass overhead on their way to Occupied Europe. Being a fairly proficient chap, he manages to score a couple of hits.
Needless to say, it isn't long before Bomber Command gets wind of Pvt. Hilton's activities, and they send a very angry Group Captain round to have a talk with him.
"Hilton, you blasted idiot! What the bloody hell are you doing firing at our aircraft!" the Group Captain demands.
"Well, sir," Hilton replies earnestly, "what I reckoned was, this is just the sort of thing our lads are going to be facing from Jerry once they cross the Channel. And if they can't take it from me, they certainly won't be able to stand up to Jerry. So, better we find out now while the lads are still on our side of the Channel."
The Group Captain thought this over, then finally said, "I suppose you've got a point, at that. Right then, Private. Carry on!"
"Yes, sir!" Hilton said with a salute, then went back to manning his gun.