"'When I use a word,' Humpty Dumpty said, in a rather scornful tone, 'it means just what I choose it to mean – neither more nor less.'"
Occasionally, our language and pesky dictionary definitions seem to pose problems for our elected officials. President Bush, educated as he was, often seemed hopelessly tongue-tied. We all remember President Clinton's "It depends on what the meaning of 'is' is." That's facile and interesting, but it falls under the linguistic category of "parsing."
Other, more recent examples are not as subtle and are more troubling – falling into the far more dangerous category of "expediency."
In an interview on ABC, (9/20/2009) George Stephanopoulos asked President Obama about charges made that the health care plan that was (then) being debated in Congress amounted to a tax. Stephanopoulos asked how the president could square this with his oft-repeated campaign stump speech pledge against raising taxes on people earning $250,000 or less.