"A couple of months ago, Sen. Clinton called me naive and irresponsible for taking this position," said Obama. "[She] said that we could lose propaganda battles if we met with leaders we didn't like."
Obama was referring to Clinton's criticism of him after he said in a July debate that he would meet with controversial world leaders without preconditions.
"Just yesterday, though," Obama continued, "she called for diplomacy with Iran without preconditions. So I'm not sure if any of us knows exactly where she stands on this."
That wasn't the only shot Obama took at Clinton in a speech marking the fifth anniversary of congressional authorization of the war in Iraq. (Related: Obama: It's time to show where I differ from Clinton)
He also went after Clinton for being the only Democratic candidate for president currently supporting an amendment that contains strong language against Iran.
The Kyl-Lieberman amendment, according to Obama, provides another blank check to the current administration. The Illinois senator claims it could give President Bush an excuse to keep troops in Iraq "as long as they can point to a threat from Iran."
Responding to the criticisms, top Clinton adviser Howard Wolfson said, "When Sen. Clinton used the term "no conditions," she was referring to meetings between the United States government and Iran, not personal meetings with the President. She was striking a contrast with President Bush who has refused to allow the U.S. government to talk to Iran about its nuclear weapons program. Senator Clinton has repeatedly said throughout this campaign that she would re-engage the world diplomatically and end the cowboy approach to diplomacy that has been used by the Bush administration."
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– CNN Iowa Producer Chris Welch