Obama in his first week said three words that the previous four presidents had avoided: “I screwed up.” Even though the Bushes, Clinton and Reagan had made massive errors — from adultery in the White House to launching a war on erroneous premises — they invariably described the mistakes in the passive voice. “Mistakes were made,” Ronald Reagan famously said, referring to his secret policy of providing arms to terrorist kidnappers.

Some pundits will view this primarily as a sign of Obama’s incompetence or weakness. I hope not. To me, it’s a sign of great strength and self confidence, and politically shrewd.
It may also be a sign of faith. A central idea of Christianity is that we’re all sinners, and what matters is ackowledging the defect and aspiring to better behavior. Of course, what Obama did — improperly vetting his nominees — isn’t a sin so much as a mistake.
But the idea of confession-as-exercise-in-humility still applies. Recall that when Obama stuck a short prayer in the wailing wall, he asked God to help “guard against pride.” At the end of the day, Christian humility flows from the idea that we’re all sinners and that it’s futile to hide one’s errors from God.
Admitting error isn’t a sign of weakness, it’s a sign of humanness. Not admitting error doesn’t mean you’re error-free, it means your dishonest.
p.s. I know other faiths also stress honesty and confession; I’m focusing on Christianity because Obama is Christian.