Remarkably, he lived to tell his tale to Rosalind Scutt.

In Operation Anaconda you and your men were surrounded by the Taliban for 18 hours, in which time you fought off many attacks. You received a Medal of Gallantry for your conduct. What was your darkest hour?
There was a point around last light when we were surrounded and I wasn’t sure that our position wasn’t going to be overrun. So I took a grenade and armed it, not only for the purpose of booby trapping my body in the event that I was whacked from behind, but also so it was ready to use in close combat. That was the darkest hour, but there were many throughout that day that were equally dangerous.

As an SAS soldier you are trained to kill. How are you taught to kill your enemy without hesitation?
With each operation comes rules of engagement that define your enemy for you. You are given specific orders and you react only according to your rules, the rules of engagement. The rules are very fair and clear cut. A soldier does not have the luxury to question orders.

History has shown that orders and intelligence can be wrong. In Operation Anaconda, the enemy was larger in numbers and better prepared than you were advised. Some say it was a miracle you made it home…
Yes, the intelligence was definitely wrong. There are no certainties in war.

What’s the difference between a regular soldier and an SAS soldier?
Primarily the roles of the units are different, so we have different training and equipment. The training itself is designed to be challenging, to enhance your effect on the battlefield and to preserve your life and those around you.

Can women work as SAS soldiers?
With the role of the job and the workload, I don’t think there will ever be women SAS soldiers in Australia. That doesn’t mean that women are not able to do their part. That’s not to say there are not army units and roles that are better suited to women.

Is it difficult to slip back into regular life after being on the front line?
There are many challenges associated with coming home, but the army has structures in place and does extensive debriefings that allow you to be aware of these changes, so you are able to deal with them when they arise. There’s a great network out there to assist you.

Has being in the SAS put a strain on your personal relationships, and has it kept you single?
Yes, that’s correct. I found it much easier to be able to go away when I didn’t have to worry about loved ones at home. But a lot of the men I have worked with have families and regular lives. 

When you were a boy, what did you want to be when you grew up?
It’s very cliched, but I wanted to be a fighter pilot. Then I found out that you had to go to school regularly and achieve high marks – so I ended up with another vocation.

How does you mother feel about your career choice?
She has always had the greatest confidence in me. She had to sign a consent form when I first joined the forces, because I was a minor in 1987 -I was 17. She has always been concerned, but she is always supportive.

Are you able to keep in touch with family when you are on assignment?
It’s not always possible to contact loved ones because the information about location and what we are doing is obviously limited for operational security. 

How do you feel when you read stories about allied troops committing atrocities on innocent Iraqi civilians? Do you lose a faith in the institutions you have been taught to believe in?
No, I definitely do not. It’s disturbing to hear, but often the media don’t get it right. It can be a beat up. But the Australians operate well, we haven’t been involved in such situations. I think that both allies and enemies alike respect the way Australians operate. I don’t think you will find any allegations in that manner about the Australian troops arising in the future.

Do you ever question the morality of this war?
Soldiers don’t have that luxury – we follow orders. If the public has a beef with the war itself, they should take that up with the politicians. With the Vietnam War you saw the anger of the population vented on the soldiers, that’s not right, they were following orders.

The “War on Terror” is a complicated war which has been brewing for decades. Do you think this is a war that can ever be won?
This is definitely a different style of warfare. How far it has spread and the amount of people who are now involved is not yet known. There’s certainly a lot of work to be done. In order to win this war you have to treat the cause and not the symptoms. We were addressing the symptoms. You can see that Al-Qaeda are going way beyond any previous methods of destructive warfare. So methods to deal with them will have to be developed over time.

In battle, do you have any mantras?
Never give up trying. You haven’t failed until you stop trying.

18 Hours by Sandra Lee is the account of Martin Wallace’s part in Operation Anaconda, and his fight to survive against al-Qaeda in Afghanistan. Published in Australia by Harper Collins.