The following is a commentary by ABC News' Sam Donaldson. Click here to view a video version of Sam's latest essay
Lindsey Graham, the South Carolina Republican senator who supports John McCain, has a suggestion: Why doesn't Sen. Barack Obama, who has visited Iraq once -- two years ago -- go back again with Sen. John McCain, who has visited Iraq eight times to get an updated briefing on the situation.
Not a chance!
I can see it now, the professor instructing his callow student -- see here, young man, this is an IED that is killing our soldiers and now let's stroll once again through the marketplace, which is so peaceful thanks to the surge which is working, which, as I recall, you oppose.
No, Obama will have to go back to Iraq before long -- if for no other reason than to say he's seen the latest -- but not in John McCain's classroom.
Iraq will almost certainly be one of the central issues in November -- if McCain is lucky it will remain relatively calm with casualties relatively low. But there is a wildcard named Moqtada al-Sadr, the 34-year-old Shiite leader of a 2 million man army.
When the surge began, al-Sadr instructed his army to lie low. Why fight an increased American force? But we all saw what happened a few weeks ago when al-Sadr loosed his men in Bashra and Bagdad -- violence flared, casualties spiked -- before calling another truce.
If al-Sadr does it again just before Election Day, McCain's assertion that the surge has worked will come under heavy fire. And furthermore, voters will be given a fresh reminder of why the vast majority of Americans want out of Iraq -- the Obama position.
The question this November will be how U.S. troops should get out of Iraq and not how U.S. senators should get in.
Sam Donaldson, a 41-year ABC News veteran, served two appointments as chief White House correspondent for ABC News, from January 1998 to August 1999 and from 1977-1989, covering Presidents Carter, Reagan and Clinton. Donaldson also co-anchored, with Diane Sawyer, "PrimeTime Live," from August 1989 until it merged with "20/20" in 1999. He co-anchored the ABC News Sunday morning broadcast, "This Week With Sam Donaldson & Cokie Roberts," from December 1996 to September 2002. Currently, Sam Donaldson appears on ABC News Now, the ABC News digital network, in a daily show, "Politics Live."