Australia’s most decorated soldier and accused war criminal Ben Roberts-Smith received a warm welcome as he appeared among dozens of veterans to mark the 25th Afghanistan war anniversary at a solemn service in Canberra.

Hundreds gathered at the Australian War Memorial on Sunday to mark the start of the nation’s longest military campaign on October 11 in response to the al-Qaeda terror attacks on America a month earlier.

Prime Minister Anthony Albanese used his address to pay tribute to veterans for their “courage” defending the nation, to make a difference in the “truest spirit of humanity”.

He said the September 11 attacks had “upended” the world in 2001 and insisted “Australia did what is so resolutely in our nature” to follow “friend and ally” the United States into the Middle East.

“We went to support our friend and ally. We went because we saw what was at stake,” Mr Albanese said.

“And we went on the principle that September 11 was an attack on a way of life that belonged just as much to us.

“The very freedoms that are at the heart of who we are as a people and a nation were under threat.”

As part of a multinational response after the September 11 attacks, more than 35,000 Australian Defence personnel served across related operations until 2021.

Forty-seven Australians died as a result of their service in Afghanistan and 263 were wounded.

Mr Roberts-Smith received a celebrity reception at the event, sharing hugs, photographs and signing autographs with dozens who approached him after the National Commemorative Service.

The Victoria Cross recipient was charged with five counts of war crime murder of unarmed men related to his deployment in Afghanistan between 2009 and 2012.

He had been arrested by the Australian Federal Police at Sydney Airport on April 7 while disembarking from a flight from Brisbane.

The former Special Air Service corporal told reporters his attendance was in honour of the thousands of Aussies who served their country in the operations against al-Qaeda and the Taliban.

“I’m here because tens of thousands of Australians contributed to the campaign in Afghanistan and they did fantastic work and that should never be forgotten,” he said.

“We can never forget the sacrifice that these people have made.”

Donning his more than a dozen service medals, Mr Roberts-Smith had been applauded among other veterans who had been asked to stand during a tribute led by master of ceremonies Colonel Scott Clingan.

Australian Memorial director Matt Anderson said many of those deployed to Afghanistan experienced the “very worst of war” and some “they would find difficult to put into words” after returning home.

In his powerful tribute Mr Anderson also acknowledged the complex view people could hold on the legacy of Australia’s involvement in Afghanistan.

He said while it was “worthy of reflecting” on if “a difficult and protracted war” was worth it following the fall of Kabul, Australia shouldn’t take away from the efforts and sacrifices of our diggers.

“Whatever conclusions are ultimately drawn by history about the campaign itself, there’s one part of the Afghanistan story that, to me, is already clear: the great success of Afghanistan is the men and the women who serve there,” Mr Anderson said.

A Chinook helicopter — commonly used to move Australian soldiers deployed in Afghanistan and often remembered as a sign of relief, resupply or reinforcement — flew over the service during the wreath laying ceremony.

Mr Roberts-Smith had also been among those to lay a wreath at Stone of Remembrance, sharing a kiss with partner Sarah Matulin after returning to his seat.

Liberal frontbencher and a former SAS veteran Andrew Hastie, who testified against Mr Roberts-Smith in his defamation trial, was also a VIP guest at the service and laid a wreath.

Mr Hastie was joined by a handful of current parliamentarians, including Opposition leader Angus Taylor, Defence minister Richard Marles, Liberal MP Phil Thompson, Nationals MP Michael McCormack and Burt MP Matt Keogh.

Mr Thompson, who is a fellow Afghanistan veteran, had been among those to pose for photos with Mr Robert-Smith which he later insisted to The West had no underlying political meaning to.

Former Liberal PM’s John Howard, Tony Abbott and Scott Morrison were also in attendance.

Mr Howard, who was in office when the decision to send Australian troops to Afghanistan was made, told reporters that Australia played an important role in following allied forces into the Middle East after the 9/11 attacks to “defend freedom”, “greater opportunities for democracy” and “greater opportunities for women”.

“It’s always worth putting your hand up to defend freedom. One of the things that makes us different is its simple commitment to the equality of men and women,” he said.

The service comes after the war memorial officially opened its dedicated gallery on the Afghanistan conflict earlier this year, which Mr Roberts-Smith had received a court bail variation to attend but eventually pulled out.

At the heart of the display is the wreckage of a bushmasters vehicle which had been destroyed by an improvised explosive device in 2012.

The driver who survived the attack, Matthew Clarke, had attended the service on Sunday after driving from Newcastle at 3am with fellow veterans.

Mr Clarke had been medically discharged after injuring his legs in the attack which he still feels the effects of more than a decade later but told The West he felt lucky it wasn’t worse.

“I was 27 when I was deployed. We were on a resupply mission, just picking up some extra equipment.

“We were driving out in the open, a long way from everything, so you could see for miles.

“Everything was very calm, eventless, and then just out of nowhere ‘bang’ there was a massive explosion.

“I looked down at my right foot and it’s shaking uncontrollably. Then I looked at my left foot and it was snapped and sideways.

“I was pulled out of the vehicle, put on a stretcher and picked up by a Black Hawk helicopter.

“I was pretty lucky considering what had happened. Other boys had times where they’ve got out of the vehicle to search for secondary explosives, and then faced incoming rounds.”

He said it was good to reflect on the campaign and catch up with familiar faces.

Janny Poate, whose son Private Robert Poate was killed in the war, spoke about her grief and the importance of families back home for “formed part of the story”.

“The empty places that remain and the grief that fills that space has become part of the everyday life for these families, including my own,” she said.

“We remember those families and loved ones who experienced the overwhelming loss of a family member who never came home and those who have suffered loss since.”

In an impassioned speech by veteran Kahlil Fegan he illustrated the tough conditions deployed soldiers faced, which included from a freezing winter to scorching summer.

He said “cowardly and indiscriminate improvised explosive devices” was always a hidden threat, as were suicide bombings, recalling one undertaken by a “child bomber”.

He, like Mr Anderson, noted the complex feelings veterans experienced after watching the fall of Kabul in 2021 but insisted no political outcome should diminish diggers service.

“Like many veterans, I watched the fall of Kabul in August 2021 with profound sadness. The images of the Taliban returning to power stung deeply,” Mr Fegan said.

“Questions emerge that many veterans still ask themselves today: Was it worth it? What did we achieve, and how will we be remembered?

“The truth is that wars are often judged by their endings, but for veterans, the worth of their service cannot be measured solely by political outcomes at the end of a war.

“It is far more complex than that.

“We can never forget that for more than two decades, our Australian service personnel and their colleagues helped deny terrorist organisations the haven they once enjoyed.

“They showed what an alternative future could have looked like.

“No political outcome can erase those facts. No headline can diminish the courage shown. No passage of time should cause us to forget.”

He said the people who served in Afghanistan “endured hardship, fear, loss, and sacrifice” and “served honorably”.

Returned Services League president and former State Labor MP Peter Tinley, who also laid a wreath at the memorial on Sunday, is expected to address the National Press Club on Monday.

He is expected to use the address titled “The missing line of defence: The duty nobody holds” to call for Australia to improve its national preparedness.