In the world of politics, when you catch an opponent in a perilous mistake, there is an art to slipping the stiletto into your opponent between the third and fourth ribs and twisting it. A gifted politician can do this with such finesse that the opponent doesn't realize he is dead until he hits the ground. It's an important tool in a good politician's toolbox.
Gov. Palin understands the correct usage of this tool, and she does it with the required finesse. I actually pity poor Hillary. The ground is approaching her face at high speed.