You know what's interesting?
Finding the true humor in that requires more than a passing familiarity with WWII history.
I've passed it along to a lot of folks, and many didn't get most of the jokes.
Not everyone is familiary with how amazing the United States' war mobilization was in the context of its economic difficulties. The motor of capitalism is truly amazing, and many don't get it.
Dozens weren't familiar with the surrender demand or the one-word response during the battle of the bulge.
And more than I can count weren't familiar with Patton's demise so as to recognize its reference in that bit of humor.
If it is true, as I believe it is, that those who don't know history are doomed to repeat it, then we're in a lot of trouble because, this crowd being a general exception, much of our society simply doen't know or grasp the history of the most profound world conflict of the last century.