Here's a quote you'll probably remember:

"I have earned every cent. And in all of my years of public life I have never obstructed justice," Mr. Nixon proclaimed, pounding his fist. "People have got to know whether or not their president is a crook. Well, I'm not a crook. I've earned everything I've got."

Then there's this flashy piece of prevarication: "I'm going to say this again: I did not have sexual relations with that woman, Miss Lewinsky," President Clinton swore. "I never told anybody to lie, not a single time; never. These allegations are false, and I need to go back to work for the American people."

(You can view Nixon's emphatic denials and Clinton's finger-shaking on YouTube. The clips are surely worth reviewing in the context of recent political skullduggery.)

What Richard Nixon and Bill Clinton had in common was their ability to lie with absolute conviction. But the truth is, I didn't believe Nixon when he said he hadn't obstructed justice, and although I wanted to believe Bill Clinton when he said he hadn't had sex with "that woman," I knew in my heart he was lying. Both men had, by that time in their respective presidencies, forfeited the trust of the American people.

These days, when a politician opens his mouth, we automatically activate our internal lie detector. We're sensitive to every word, every hand gesture, every faint smirk. So when I heard that Obama had strongly repudiated his pastor, Jeremiah Wright, I went surfing for a verbatim transcription of his press conference.

What I found went, in part, like this: "I want to use this press conference to make people absolutely clear that obviously whatever relationship I had with Reverend Wright has changed, as a consequence of this. I don't think that he showed much concern for me. I don't -- more importantly -- I don't think he showed much concern for what we're trying to do in this campaign and what we're trying to do for the American people and with the American people."

But how Obama delivered his remarks is quite different: "Well, the, uh, uh, I, uh, uh, want, uh, to use this press conference to make people absolutely clear that, uh, uh, obviously whatever relationship I had with Reverend Wright has changed, as a consequence of this. Uh, I don't think that he showed much concern for, uh, me. I don't -- more importantly -- I don't think he showed much concern for, uh, what we're trying to do in this campaign and what we're trying to do, uh, uh, for the American people and with the American people." And a lot more hemming and hawing followed.

Despite his hesitations and his slightly hangdog demeanor, I continue to believe in Obama's sincerity. I believe he's telling us the truth as he sees it, although I'm not certain that he, Hillary or anyone else can end the war in Iraq or solve the health-care conundrum.

It's the Friday before the North Carolina primary as I write this, and I've watched the video of Obama's press conference four or five times. (You can view Obama's remarks at http://www.youtube.com/watch?v=qWRs7tB_zaw.) Obama's delivery lacks the Nixon/Clinton bluster. He sounds worried, almost desperate, and decidedly uncertain of himself, traits that aren't reassuring to voters, who are, more than anything else, longing for a competent, straightforward, self-assured president.

Obama's detractors -- especially the gang at Fox News who would have us believe that he's the secret two-headed love child of bin Laden and Paris Hilton -- have implied that Obama is lying about his refutation of Wright and the anti-American slop the pastor espouses when he says that Obama believes blacks should not sing "God Bless America" but "God damn America," that the U.S. government has a program to infect the African-American community with HIV/AIDS, and that the Nation of Islam leader Louis Farrakhan is a great American.

As I write this, the polls indicate that Clinton is out in front in Indiana and that Obama is ahead in North Carolina. We're told there's little doubt that Clinton will win the Indiana primary, so the voting in North Carolina will be a referendum on Obama's believability. Do we trust that he's telling us the truth or do we believe he's just another politician who'll say anything to get elected?

By the time this piece appears in The Pilot, we'll know the answers to those questions.

Stephen Smith can be reached at travisses@hotmail.com.