As President Barack Obama struggles to lead the country through a struggling economy, his critics have been all-too-quick to make an invidious comparison to another Democratic president, Jimmy Carter.

But slurs against Mr. Carter are two-edged; they also bring to mind some sunnier qualities. Of all presidents, the good-hearted Mr. Carter is arguably the best ex-president the nation has ever had. That he has worked his latest magic in the paranoid, despotic communist fiefdom of North Korea only adds luster to his reputation.

Mr. Carter has made a post-White House career of humanitarian efforts and has visited North Korea before -- in 1994, when he met with the late President Kim Ill Sung, father of the current leader, Kim Jong Il, and paved the way for an agreement that for a time froze North Korea's nuclear weapons program.

This time his private humanitarian mission was able to win the release of an American, Aijalon Gomes, 31, who was arrested after crossing the border without permission seven months ago.

According to the official North Korean news agency, Kim Jong Il approved the release of Mr. Gomes, although it did not report that Mr. Carter met with the mysterious North Korean leader. Still, he was received warmly and he did meet with North Korea's No. 2 official, Kim Yong Nam, who expressed interest in resuming the six-nation disarmament talks, and other top officials.

Former President Bill Clinton had a successful visit to Pyongyang last August, winning the freedom of two American women. As private citizens, former presidents have the prestige to impress the most unyielding of leaders, yet without carrying the baggage of putting the United States in a position of officially condoning any behavior. They are ice breakers -- and isolated North Korea is a place that desperately needs it. For Jimmy Carter, it was a job well done.

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