Senator Joe Lieberman announced today that he will not seek reelection in 2012. But he’s a Man in Full -- at the top of his game -- whose talents president should tap. 

Lieberman is one of a handful of American leaders respected around the world by friends as well as foes. He’s had a storied career as a 25-year member of the Senate Armed Services Committee; as a vice presidential candidate who came within a whisker of winning; and as one of the only men in American who has managed to chart a course between the liberal left and conservative right. And he is someone universally thought of as a politician of integrity in an era when most Americans give politicians, especially those in Congress, a single digit approval rating.

My husband and I had the opportunity to spend some time with the Liebermans in Israel two months ago, at private dinners with leading Israeli businessmen, political leaders and defense officials. Their respect for him was palpable, even when he told them things they didn’t want to hear.

When Defense Secretary Robert Gates retires sometime this year, his departure will leave a large and gaping hold in the Obama cabinet. The president needs to appoint someone who won’t miss a beat in dealing with two ongoing wars, a defense budget in decline, a foreign policy under assault, and Congress often at odds with the White House. He will need someone with experience abroad as well as on Capitol Hill, and someone who can hold his own in the a high powered Cabinet.

Senator Lieberman? It’s time to make that Secretary Lieberman.

Kathleen Troia "K.T." McFarland is a Fox News National Security Analyst and host of FoxNews.com's DefCon 3. She is a Distinguished Adviser to the Foundation for the Defense of Democracies and served in national security posts in the Nixon, Ford and Reagan administrations. She wrote Secretary of Defense Weinberger’s November 1984 "Principles of War Speech" which laid out the Weinberger Doctrine. Be sure to watch "K.T." every Monday at 10 a.m. ET on FoxNews.com's "DefCon3" already one of the Web's most watched national security programs.