D-Day, 6 June 1944
During the buildup for the invasion many thousands of Americans invaded England. The British said at the time that there were three problems with having so many Americans in Britain.
The Americans are 1) over paid, 2) over sexed, and 3) over here
In general they were happy to have us on their little island as it signaled the beginning of the end of WWII for the beleaguered British. They had stood alone for far too long against an enemy that occupied most of Europe.
The D-Day attack was close to failure, perhaps too close for comfort. If the German Panzer reserves had been sent to the beachheads the troops landing would have never survived the attempt. Luckily enough for the Allies, only Hitler could give the order to use the Panzer reserves, and nobody wanted to wake him up and ask. Weird, but true.
My father was in the South Pacific at the time. He never spoke of his wartime memories, so I assume that they were painful.