A speech in Nashville, Tennessee, Sept. 17, 2002, President Bush once referred this quote to have been come from Tennessee or Texas, I looked it up on google and couldn't find a good reliable source. The closest one I've gotten claimed it came from the chinese:
一回愚我，汝之耻；二回愚我，吾之辱。(Supposedly by Confucius, but no further citation could be found. Hence, it is doubtful that Confucius actually said it or if this phrase was the verbatim quote)
It was also quoted in this Startrek series where Scott said it and Chekov attributed it to the Russians.
Hence the real saying goes:
Fool me once, shame on you; fool me twice, shame on me.
Unfortunately, Bush seemed to have had a mental block and went:
fool me once, shame on — shame on you. You fool me you can't get fooled again!
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