Republican leaders tiptoe around the smear campaign against Obama's faith and citizenship.

The party that was supposed to stand up to President Obama can't even stand up to its own fringe.

Six months ago on Meet the Press, NBC's David Gregory asked Senate Republican Leader Mitch McConnell about a survey in which 31 percent of Republicans said President Obama was a Muslim. McConnell demurred: "I think the faith that most Americans are questioning is the president's faith in the government to generate jobs." Gregory persisted: "As a leader of the country, Sir—as one of the most powerful Republicans in the country—do you think you have an obligation to say to [31] percent of Republicans in the country … who believe the president of the United States is a Muslim, 'That's misinformation'?"

The best McConnell would do was this: "The president says he's a Christian. I take him at his word."

Reviewing the exchange in Slate, my colleague John Dickerson tartly observed: "If McConnell wasn't trying to stir the pot, he also wasn't trying to lower the boil."

Well, that was half a year ago. And McConnell was just one Republican leader. And if he didn't explicitly denounce the Obama-Muslim conspiracy theories, as Gregory had requested, perhaps that was a result of being surprised by the question.

But since then, the leadership's pattern of cowardice in the face of Obamaphobic falsehoods has grown.

On Jan. 6, John Boehner's first day of business as speaker of the House, a heckler in the chamber challenged Obama's citizenship. NBC's Brian Williams asked Boehner: "You've got 12 members co-sponsoring legislation that does about the same thing: It expresses doubt [about Obama's citizenship]. Would you be willing to say: 'This is a distraction. I've looked at it to my satisfaction. Let's move on'?" Boehner replied: "The state of Hawaii has said that President Obama was born there. That's good enough for me." For me, lest anyone feel that the speaker was imposing his personal beliefs.

Williams persisted: "Would you be willing to say that message to the 12 members in your caucus who seem to either believe otherwise, or are willing to express doubt and have co-sponsored legislation?"

Boehner answered: "Brian, when you come to the Congress of the United States, there are 435 of us. We're nothing more than a slice of America. People come regardless of party labels. They come with all kinds of beliefs and ideas. It's the melting pot of America. It's not up to me to tell them what to think."

Not up to me. Obama's citizenship, like one's religion or favorite color, is a matter of personal belief. Think what you want to.