War in Iraq 'different' this time: US military chief insists
Iraqi and US soldiers at a joint US-Iraqi military exercise on April 18, 2011, south of Baghdad (AFP Photo/Ahmad al-Rubaye)

US military action in Iraq has a better chance of success than the last war there because American troops are playing a supporting role to local forces from the start, top officer General Martin Dempsey said Wednesday.

The chairman of the Joint Chiefs of Staff also voiced cautious optimism that Iraqi forces were gaining strength and predicted they would make progress on the battlefield in the coming months against the Islamic State group.

Asked at a Washington conference why Americans should expect the latest US intervention in Iraq to go better this time, Dempsey said "we think we're taking a different approach."

"Instead of grabbing a hold of it, owning it and then gradually transitioning it back, we're telling them from the start, look, that is about you, this has to be your campaign plan," the general said at a conference organized by the Defense One website.

As an example, Dempsey cited an episode that played out during his recent visit to Iraq over the weekend.

The Iraqi army asked for US assistance to parachute supplies to about 1,300 Kurdish forces on Mount Sinjar in the country's north, he said. But the American commander in Baghdad pointed out that the Iraqis had a C-130J cargo plane and trained pilots that were capable of carrying out the mission.

"As this unwound, what the commander on the ground ... said was, 'We'll provide you with the expertise for what you don't have, but you have what you need to accomplish this mission,'" Dempsey said.

"And so the only thing we provided at that point was the expertise to actually rig the parachute extraction system that would do the air drop."

The outcome reflected the difference in the US approach compared to the 2003 US invasion and the occupation that followed, he said.

"So they do what they can do, and we fill in the gaps and continue to build their capability," said Dempsey, who led troops in Iraq in the previous conflict.

- 'Some tactical success' -

President Barack Obama has ruled out a large US ground force in Iraq but has backed air raids against the IS group and sent in hundreds of military advisers to help Iraqi forces.

US-trained Iraqi army units suffered humiliating defeats earlier this year when they were overrun by Islamic State jihadists in the west and north, but Dempsey said Baghdad's forces had been shored up and new commanders were being named.

Iraqi troops are "having some tactical success" and are "pushing the defensive belt around Baghdad out," he said.

"They are doing much better. But they've still got, as I said, some deep structural vulnerabilities that we, but mostly they, have to overcome."

He warned that it was important that "their enthusiasm doesn't overshadow their capability at this point."

With US and coalition assistance, "I think there will continue to be progress on the ground" over the next few months, the general added.