I think he explains himself quite well:
He’d joined the army, he says, like many, to earn money, as ‘a way out of a boring lifestyle and menial labour’ and also to serve his country, ‘the idea of Britain as a force for good, liberty and democracy’.
His tour lasted seven months. His experiences changed how he saw Britain’s involvement in Afghanistan.
‘We knew civilians were being bombed and how the war was being conducted,’ he said. ‘It was conducted in a climate of racism and indifference to the Afghan people, completely at odds with how it’s sold at home. I came back and because of those things, I thought, “No, this isn’t right”.’
"We’re told we’re going there to help young girls get an education or to build infrastructure or really hackneyed stuff like security there equals security here.
‘Let’s look at probability. Does the US, with Britain in tow, go to Afghanistan to help women go to school or is it because there is, for example, 90 billion barrels of oil in the Caspian?
‘Is it human rights or is it because Afghanistan is in a strategic location with borders with China, Pakistan and Iran? Are we spreading democracy or is this power politics? It’s a new veneer on a very old practice.’
So maybe if the reality of the situation were more widely known, perhaps less people would sign up. Our media aren['t tellng us the whole story, that's for sure, so there' a lot of ignorance and misinformation about what's really going on there. Seems like this guy had a road to Damascus conversion, and didn't want to be a part of it any more. What was happening wasn't what he'd signed up for, or been told. So he was in effect lied to, mislead, decived. I doubt so many would be willing to sign up if they knew the truth about what is really happening there.
Interesting article linked:
Israel wouldn't have an army if there wasn't enforced conscription. Israel wouldn't exist if it didn't have an army. But what about an individual's right to refuse to take up arms against another?