by Tahman Bradley and Jacqueline Klingebiel

Barack Obama joined John Edwards on Monday in going after Hillary Clinton's support for the Kyl-Lieberman amendment, which designated the Iranian Revolutionary Guard a terrorist organization.

"Senator Clinton obviously in 2002 voted to authorize the war in Iraq," Obama told ABC News' Sunlen Miller. "And her willingness to once again extend to the president the benefit of the doubt I think indicates that she hasn't fully learned some of the lessons that we saw back in 2002."

"We have to be very cautious in how we approach these kinds of issues, because we've already seen enormous damage done to US's prestige around the world, the US's strategic interests in the world," he added. "Part of the reason Iran has been strengthened is because of that war that had been authorized in Iraq."

Asked why he missed the vote on the Kyl-Lieberman amendment if it was so important, Obama said, "Well it wasn't a close vote. One of the things about running for president is there will be votes all the time that aren't close. I put out a statement very clearly in terms of my opposition and I think it's important for us to send a signal to the world that we are not expecting to solve every problem militarily."

Edwards himself stepped up his attack on Clinton in an interview on "progressive" radio.

"You've got George Bush out there rattling his saber about going to war in Iran. The last thing we need to do is give that guy any authority on the first step to move forward. So, I do differ with Senator Clinton about this," said Edwards on The Ed Schultz Radio Show.

Moments after Edwards was on the program Randall Rolph, the registered Democrat who pressed Clinton about her vote on Sunday, told Schultz that Clinton "barked" at him and made it seem like he didn't know what he was talking about. Rolph also accused Clinton of representing "more of the same" as the current Bush administration.

So far, Edwards has focused his fire on Clinton. But now that Obama has begun to wiggle his way into the story, will the Southern Smootie go after Obama for missing the vote?
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