Australian elite commandos are battling Iraqis in "shoot-and-scoot" missions deep behind enemy lines, air force pilots are pounding enemy positions and navy divers are swimming through murky waters hunting anti-shipping mines.

Yet, each morning of the 16-day old conflict, Australian military spokesman Brigadier Mike Hannan opens his media briefing in Canberra on Australia's 2,000-strong commitment to the Iraq war with these words: "I'm happy to report there have been no major incidents or casualties in the past 24 hours."

The U.S. casualty list is now 73 dead, eight missing and seven captured. The number of British dead is 27.

David Horner, a professor of military operations at the Australian National University, said the absence of Australian casualties is not just due to the relatively tiny commitment Canberra has made to the war. The United States has sent more than 250,000 troops and the British 40,000.

The vast majority of Australian forces are in non-combat roles. Of the 2,000 personnel only 150 elite special forces troops are operating on the ground in Iraq. The other personnel considered most at risk are the pilots who fly Australia's 14 F/A-18 Hornet fighter jets.

The remaining Australians are mostly well away from any action -- in support roles, on navy ships, at command headquarters in Qatar, and in maritime patrol and air transport planes.

"Most of the American and British casualties have been from infantry that are conducting battle attacks. We don't have troops in those roles," said Horner.

"We have the SAS (Special Air Service forces) but they are small and specialized. Their job is surveillance and reconnaissance. They fight if cornered, but their job is to avoid contact with the enemy if possible," he said.

"Infantry don't have that luxury, if there's a hill that has to be captured they have to capture it even if it means loss of life," he said.

Horner said special forces troops also tend to be in their late 20s or early 30s, while infantrymen are more likely to be young men aged from 18 to mid-20s.

"They are older, wiser, street smart," he said.

Horner said that in Vietnam, 600 Australian SAS served alongside U.S. forces from 1966 to 1971. Only one was killed by enemy fire.

In that time they had 298 contacts with the enemy, killed at least 492 -- possibly up to 600 -- wounded 47 and took 11 prisoners.

The lack of Australian casualties is a political blessing for Prime Minister John Howard who has relentlessly supported U.S. policy on Iraq and committed Australia to the war despite overwhelming public opposition.

According to polls, in the past two weeks public opposition to Australian involvement in the war has fallen from around 70 percent before the hostilities began, to just under 50 percent.