The 11 September 2001 was not a particularly remarkable day for me. I had been living in Kabul, Afghan­istan with my wife and children since June that year, working on establishing a school which catered for both girls and boys under the strict rule of the Taliban.

Two days before 9/11, however, there was heightened tension after it was announced that the Northern Alliance leader, Ahmed Shah Massoud, had been assassinated by al-Qaeda. I was told that things might get unsafe for foreign Muslims. I had no idea how unsafe . . .

On 9/11, I was sitting at home playing with the children when I heard a sharp banging on my front door. It was my friend and housemate Shaker Aamer, in an alarmed state, telling me that the US has been attacked. Who could "attack" the US, I wondered. Was it China, Korea, or Cuba, even? I'm ashamed to admit I'd never heard of the twin towers, and I didn't see the images of the attacks until I arrived in Pakistan several weeks later: the Taliban had banned television in Afghanistan.

The world has been living with the consequences of that day ever since. Now, at least, I'm a free man. A decade later, Shaker Aamer, who had once informed me of events that were to change our lives, remains a prisoner in Guantanamo - without charge, trial or hope of release any time soon.

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