OPINION: It was 6am on September 12, 2001, when my phone rang and Gerry Brownlee said “turn on the TV, the US is under attack”.

The Twin Towers had fallen. Later that morning we talked about what it meant. Was it like Pearl Harbour? We decided no, in these circumstances, international terrorists could not start a world war. But we knew the world had changed. New Zealand would have to stand with its traditional allies and partners.

Later that day, there was a special debate in Parliament led by the deputy prime minister, Jim Anderton, standing in for prime minister Helen Clark who was overseas. When Jim Anderton said, “New Zealand will stand with other democratic nations to do whatever is necessary to prevent and remove … the devastating scourge of terrorism,” I knew that New Zealand would be going to war.

Afghanistan was the base of the Al Qaeda terrorists who had struck the United States. The SAS were the first soldiers to go to Afghanistan. They were deployed in December 2001, a few days prior to the formal United Nations authorisation of force. Over the next decade, the SAS were deployed to Afghanistan three times. Two of them lost their lives in 2011. Corporal Apiata was awarded the Victoria Cross for rescuing a severely wounded comrade and carrying him to safety through intense machine gun and rocket fire.

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The Provincial Reconstruction Team (PRT) was deployed to Bamyan Province in September 2003 and left in 2013 after 21 rotations. Over 3000 New Zealanders served in the PRT during the 10 years it was in Bamyan. In one terrible 10-day period in August 2012, five members of the PRT were killed. Over the 20 years, 10 New Zealand service people lost their lives in Afghanistan and many more were wounded.

Many have asked, was it all worth it?

As Minister of Defence between 2008 and 2011, I visited Afghanistan twice. I also recommended to Cabinet that the SAS should be deployed for their third deployment to help secure Kabul and to protect the PRT. The Operation Burnham Inquiry was held into how the largest SAS operation, intended to protect the PRT, was carried out, and how it was reported back to New Zealand, including the responsibility of myself as minister.

On my visits to Bamyan, I saw an impressive level of progress. Schools and health clinics had been built throughout the province. The provincial capital, Bamian, had a new hospital and polytechnic. The major centres were linked by new sealed highways and there was a new solar electric system. Elections were held. The lives of the people of Bamyan were hugely improved. But material prosperity was not a sufficient inducement for everyone. The Taliban insurgency became worse and worse, resulting in the death of eight members of the PRT between 2010 and 2012.

The 50 nations who committed forces to Afghanistan essentially forgot why they went in the first place. Jim Anderton had identified the key issue on the day of the attacks on the United States, which was to defeat terrorism. Instead, the goal became to build Afghanistan into a modern state, on the basis this was the best way to defeat terrorism in the long run, that the terrorists would find no safe haven in Afghanistan. It was a laudable goal. However, the last two decades have shown it is not possible to impose a new style of state upon a people without their virtually universal consent.

Yes, the material lives of the people of Afghanistan have been substantially improved, with hundreds of billions spent on infrastructure and improved social systems. Yes, there is a democracy of a sort. However, a substantial minority of the Afghan people have always wanted us gone and have fought for many years to send the international forces home.

New Zealand forces are leaving Afghanistan, as will most of the other international forces over the next 18 months. The original intention of ensuring Afghanistan is not a safe haven for international terrorists has largely been achieved for the time being.

In the recent peace agreements, the Taliban has accepted the importance of keeping Afghanistan free from international terrorists. However, the real proof will emerge over the next decade. Only then will we know if Afghanistan has been able to resolve its internal differences, and whether the wider world will be able to think about Afghanistan without a sense of anxiety.

Wayne Mapp is a former National Party MP and Cabinet minister.