What it proves is she has more guts to stand on conservative principles than other candidates.
It's disgusting Bachmann haters have to attack her for doing the right thing.
All this story proves, taken to its logical conclution is that this Stephen Clark and Fox News are attacking Bachmann, and that Bachmann probably fell into a trap set for any candidate who was so incautious to sign the pledge, which was probably carefully written and worded by a democrat mole.
The statement reveals that slavery was evil, but social engineering is more evil. The fact that socialism is more evil in no way minimizes the fact that slavery is evil. Sadly, the slave population has been moved from one plantation on to another, the government plantation, which is ultimately even more destructive. Socialism makes everyone slaves; at first a kinder gentler slavery, but eventually cruel and nihilistic.