Obama: Hope and anger go hand in hand.

I love the fact that Obama is simply refusing to back down over this.

"I talk about hope a lot in this campaign. Hope is not blind optimism. Hope and anger go hand in hand. You've got to be angry about your circumstances to want to bring about change, but you've got to have hope to believe that change can happen.

Tags: Barack Obama, bitter, US election 2008, democratic presidential nominee