Senator Obama's opt-out of public financing came as no surprise. It was a politically expediant move. However, the switch is disconcerting, not just because he broke his word or changed his mind; it's troubling because he signed a pledge. When most Americans sign a 'pledge' it's considered a legally binding contract. Yet this was a 'pledge' and not a contract? So it should be noted that a pledge from Senator Obama is a non-binding agreement. Signature, no signature, this is different than changing on a position, he promised to do 'x' signed off on it then did 'y'. Politically it was most likely the right thing to do, he will have much more money this way. However, he revealed to the American people in the process that a promise, a pledge, and his word are negotiable.