a piada

George W. Bush was in an airport lobby and noticed a man in a long flowing white robe with a long flowing white beard and flowing white hair. The man had a staff in one hand and some stone tablets under the other arm.
George Bush approached the man and inquired, "Aren't you Moses."
The man ignored George and stared at the ceiling.
George Bush positioned himself more directly in the man's view and asked again, "Aren't you Moses".
The man continued to peruse the ceiling.
George tugged at the man's sleeve and asked once again, "Aren't you Moses".
The man finally responded in an irritated voice, "Yes I am".
George asked him why he was so uppity and the man replied, "The last time I spoke to a Bush I had to spend forty years in the desert".

David Minkoff, "The Ultimate Book of Jewish Jokes" (também aqui).