Democrat Barack Obama accused President George W Bush on Friday of "fear-mongering" for suggesting Democrats wanted to appease terrorists and vowed to meet leaders of hostile nations like Iran if elected.
In a long-distance foreign policy debate that ricocheted through the US presidential campaign, Republican candidate John McCain called Obama reckless and out of touch with reality, while Hillary Clinton has defended her rival Democrat.
Obama clearly relished the clash with Bush and chance to link McCain with the unpopular Republican president. He said Bush had contributed to Iran's rise in the Middle East by launching the Iraq war, which he said had removed Baghdad as a counterweight to the Islamic republic.
The Illinois senator said McCain was as much to blame as Bush for what he termed a US Middle East policy failure.
"They're trying to fool you, and trying to scare you, and they're not telling the truth. And the reason is because they can't win a foreign-policy debate on the merits. But it's not going to work," said Obama, the Democratic front-runner vying to face McCain in the November presidential election.
Obama said if elected president he would meet, with preparation but without preconditions, leaders Bush has avoided, such as Iranian President Mahmoud Ahmadinejad, Syrian President Bashar al-Assad, North Korea's Kim Jong-il and Venezuelan President Hugo Chavez.
"I would engage in direct talks," he told reporters after a speech.
Iran, Syria and North Korea are considered by the US State Department to be state sponsors of terrorism while Venezuela has stoked anti-American sentiment in South America.
Bush triggered Democratic outrage on Thursday by saying in a speech in Israel that some politicians would pursue the "false comfort of appeasement" by negotiating with militant groups such as the Palestinian Hamas and Hezbollah organisations and Iran.
Obama said Bush and McCain were guilty of "bombast, exaggerations and fear-mongering."
The White House said it was baffled at the Democratic response and that Bush had long made similar statements.
"I would encourage you to ask them what sentences that they disagree with, what specific sentence," White House counsellor Ed Gillespie said on the Air Force One flight to Saudi Arabia.
McCain's campaign accused Obama of an "hysterical diatribe" and the Arizona senator said he welcomed a debate on security.
"Talking, not even with soaring rhetoric, ... will not convince Iran to give up its nuclear program. It is reckless to suggest that unconditional meetings will advance our interests," McCain told a Tennessee meeting of the National Rifle Association.
It was wrong to believe there were no enemies in the world, he said. "Until Senator Obama understands that reality, the American people have every reason to doubt whether he has the strength, judgment and determination to keep us safe."
The episode allowed Obama to talk directly to Bush and elevate himself on the national stage as he tries to wrap up the Democratic presidential nomination. Even party rival Hillary Clinton has come to Obama's defense, saying on Thursday that Bush's remarks were "outrageous and deeply offensive."
Weakened by the Iraq war and ailing economy, Republicans hope to convince Americans that Obama is too inexperienced to be trusted as commander in chief, as McCain tried to assert on Friday.
But Obama sought to turn the experience question around on Bush and McCain.
"They've got to answer for the fact that Iran is the greatest strategic beneficiary of our invasion of Iraq. It made Iran stronger, George Bush's policies," he said.
"They're going to have to explain why Hamas now controls Gaza, Hamas that was strengthened because the United States insisted that we should have democratic elections in the Palestinian Authority," he added.
