Because bush minor is pathologically incapable of telling the truth. He has even been caught in lies when he didn't have to lie in the first place,
just to make himself look big. For example: his midnight flight to Baghdad for thanksgiving with the troops (still wouldn't surprise me if it wasn't
a body double), he claimed that the flight was almost aborted when a British Airways flight radioed over and asked if that wasn't Air Force One.
Later it came out that there wasn't another flight within 100 miles of them not to mention there is nothing that says this is air force one, it was
night and all the shades were drawn... in short it was a petty little lie to make him look bigger and braver than that pathetic little man is.

