If that joke were told as you posited, I would think that the joke was on the Nazi because he’s pretty stupid. Would we think the Jewish merchants were greedy if we inserted dumb blonds in the joke?
I’m glad you made the point that you were not comparing people like Jones, Petraeus and McChrystal to Qjuisling or Petain. As I said previously, lets judge these men by their actions. I have criticized numerous former military men on here such as Wesley Clarke, John Murtha and Joe Sestack. But I criticized them for their policies, their actions and what they believed. Not because they were associated with Obama.
You may think the joke funny, but how do you get "pretty stupid" for asking for water or "clever" for refusing water to someone in need and gaming him instead?
The blunt of this joke may be subjective but the object of it's ethical judgment is not. It is "the Jews." And someone in General Jones' position knows it.