Jeb Bush and Hillary Clinton trade blame over Iraq war

A decade of anger over the Iraq war resurfaced in the 2016 US election race on Tuesday, with Jeb Bush and Hillary Clinton's campaigns trading blame about that country's continued instability.

Twelve years after president George W. Bush led the United States into an unpopular and troubled conflict, his brother, now a Republican presidential hopeful, accused Democrats of abandoning Iraq before the job was done.

Jeb Bush blamed his Democratic White House rival, former Secretary of State Clinton, for allowing the brutal emergence of the Islamic State group by withdrawing troops from Iraq too fast.

"It was a case of blind haste to get out," Bush told an audience in California, "and to call the tragic consequences somebody else's problem."

"That premature withdrawal was the fatal error, creating the void that (Islamic State) moved in to fill."

"Rushing away from danger can be every bit as unwise as rushing into danger, and the costs have been grievous," he said.

Taking a political risk, Bush even suggested it might be necessary to send more troops back to Iraq.

"Right now, we have around 3,500 soldiers and marines in Iraq, and more may well be needed."

"We do not need, and our friends do not ask for, a major commitment of American combat forces. But we do need to convey that we are serious, that we are determined to help local forces take back their country."

He advocated embedding US personnel with Iraq forces.

Bush also noted Clinton only visited the country once during her four years as America's top diplomat.

His remarks dredged up a bitter debate that has long bubbled in Washington and that has tarnished his brother's legacy.

A wildly successful invasion of Baghdad was followed by a ham-fisted occupation that fuelled brutal sectarian violence and left the central government debilitated.

In addition to being a point of contention between Republicans and Democrats, the conflict may have also cost Clinton the 2008 Democratic nomination to anti-war candidate Barack Obama.

In 2002, Clinton voted in favor of authorizing Bush's invasion as a Senator for New York, a vote she later said was a mistake.

But on Tuesday her campaign defended her later record.

Long-time foreign policy aide Jake Sullivan -- a frontrunner to become Clinton's National Security Advisor if she is elected -- accused Jeb Bush of a "pretty bold attempt to rewrite history and reassign responsibility."

"They cannot be allowed to escape responsibility for the real mistake here," he said, saying Islamic State emerged form Al-Qaeda in Iraq, which flourished amid the occupation.

"It didn't exist before the invasion. It emerged in no small part as a result of president Bush's failed strategy. And it gained strength by signing up former Sunni military officers – officers from the army that the Bush administration disbanded," he said.