While Democrats are still squaring off over who will be the presidential candidate - Senator Barack Obama or Senator Hillary Clinton - Republican Senator John McCain has taken the opportunity to lay out some of his campaign's message. He wants to stay in Iraq, and he's questioning the leadership skills of both Democrats, who say they will begin bringing US troops home once in office.

But how? Clinton may have a little more play here than Obama. She's never said her vote for the war was wrong, presumably to avoid looking weak on national defense. And if she changed strategy once in office, a lot of Hillary-haters would say "I told you so," given the trust factor issue that continues to haunt her.

Obama is the most vulnerable. He's hitched much of his campaign to his "I didn't vote for the war" message. Fine, we got that several months ago.

David Petraeus, commanding general of the multinational force in Iraq, will testify on Capital Hill today, and it will give all three candidates an opportunity to ask the when and how questions.  

If bad judgment got us into this war, what will the decision to leave look like - presuming we do? What kind of judgment is needed now?

When the US finally pulled out of Vietnam, most of Southeast Asia was expected to fall to Communist China within months. The images of Vietnamese people desperate to escape still haunt us. But they could seem tame compared to what the 24-hour news media will report as US troops pull out of Iraq.

Many of the predictions about the aftermath of the Vietnam War didn't happen. And the truth is, no one really knows what will happen when we leave Iraq. But Americans might want to be prepared to "look away from your screen now if disturbing images bother you."

Petraeus's testimony is being aired live on WXXI.