What I was concerned about when I wrote the Downward Spiral record was being a self-centred destructive force. The point was tearing down everything in a search for something else. I had a little experiment in my life in my early 20s where I knew what I wanted to do but I was afraid to do it. I was afraid it wouldn’t be any good. I’d always been smart and knew I could get by. But I’d never pushed myself to see what I was capable of because I didn’t have to. Then I thought ‘what would happen if I get rid of all the shit I don’t need?’ I don’t need friends or girls or a band. It was like ‘fuck you’ and I became autonomous and turned inward and found all this hatred and ‘me against the world’ attitude.

And that hatred and isolation found expression in your music?

I found I could turn that into something. Instead of punching the wall and having my hand hurt, I could write it down. Strangely things came out of that seemed to have this catharsis. There was a beautiful element to it and it made me feel good. So I decided to keep doing that. When I wrote The Downward Spiral in 1993 I was five or six years into that experiment and it still worked.

The record was exploring a narrative about someone who systematically examines every aspect of their life and then destroys it on a path to trying to find some other solution. I’d started with that theme and fitted songs into the storyline, dealing with religion and sex and drugs and the record ended with some sort of conclusion that could have been suicide, but certainly wasn’t a positive place.

The one song on that record that doesn’t fit that description was Hurt, How did you write Hurt, which Johnny Cash famously covered…

The video he made of that song was overwhelming. When I saw it the power and beauty of music struck me in a really profound way. I was at a point in my life when I was really unsure if I was any good or if I had anything to say. The song came out of a really ugly corner of my mind and turned into something with a frail beauty. And then several years later an icon from a completely different world takes the song and juxtaposes himself into it in a way that seems more powerful to me than my own version. I was flattered as an artist and as a human being they could do that with my song. And it came at a very insecure time in my life and it felt like a nudge and boost and a hug from God. It said ‘everything’s OK and the world is bigger than what’s just in my head.’

So how did you write Hurt?

I wrote that after I thought the record was finished. It happened in a day or so and I hadn’t planned on it being on the record or on making a song as gentle or delicate or that. I was uneasy about putting it on the album because that song felt like I was saying I needed help. I wouldn’t admit that to myself but when I wrote it I felt like I was sitting in a pile of rubble and there was a hint of regret and remorse. Hurt was the first inclination for me that I could use a hand here. The Downward Spiral

album was a record all about beating everybody up – and then Hurt was like a coda saying may be I shouldn’t have done that. But to make the song sound impenetrable because I thought it was a little too vulnerable, I tried to layer it in noise.

That seems to be a bit of a theme with your work with Nine Inch Nails…

Well a lot of what I’ve done as Nine Inch Nails has been governed by fear. I was trying to keep the songs in a framework that was tough and I learnt a lot from Jesus and Mary Chain about how to bury nice pop songs in unlistenable noise – the idea being if you can get behind that wall you find there’s a pearl inside. That’s where my head was at.

What was behind the lyric when you wrote it? The ’empire of dirt’ was presumably the whole junkie lifestyle…

Interestingly enough, when I wrote the song I had no idea what was in store for me. I wrote the album about somebody who follows this path who was an extension of me. But it was in my head. I hadn’t actually lived it. Then later I lived it. I didn’t realise the record was a premonition. I was using the metaphor of drugs at the forefront of what was going on. But I wasn’t a junkie. Later I became one, but I didn’t know there was an addict in me that just hadn’t bloomed out of the dirt yet.

So that whole album became a self-fulfilling prophecy?

Yes. Oddly enough, that album began my own personal plummet into the depths of addiction and finding out my way doesn’t work and that I needed people and help every once in a while and I am human after all. That’s why the records since then have taken such a long time. On 1999’s The Fragile I was still lying to myself about what was really happening.

You developed a reputation for excess that was excessive even by rock’n’roll standards…

Even when you come to the end of a destructive phase of writing all those songs like that , it sticks with you. It’s not like I could say ‘I’m done writing, I’m now going to go out there and be normal.’ In my life I was always floating around the edge of the dark side and saying what if take it a little bit too far and who says you have to stop there and what’s behind the next door. Maybe you gain a wisdom from examining those things. But after a while you get too far down in the quicksand.

So how did you clean-up?

Very simple. In 2001 when we finished touring, I realised ‘you’re going to die unless you stop’. Your friend just died and there’s no more way forward You get your shit together or your die. It’s tough when you think you’re smart. I’d seen people and said ‘I’ll never be that fucking bad. I’m too smart to be an addict.’ Yet I became something I never thought I could be. It was a gradual realisation but there was a definite point where if I had any molecule of sanity left, I couldn’t deny what was right in front of my face.

Do you have to reach a point of self-loathing to take that decision to change?

You do loathe yourself because you’ve lost all self-respect. I remember thinking ‘What’s the point? I’ve had everything I ever wanted in my life and I’m vomiting in the sink again. How did that happen?’ So yes, I hated myself.

Is the new record, ‘Halo 19: With Teeth’, a chronicle of your recovery?

I hope it’s not that boring. I didn’t want to be preachy. But I can’t deny it was a huge thing behind the record. Every aspect of my life changed. I decided I would do anything not to be in this shape. I thought ‘let me not try to bend the rules and just take it easy and not think about making a record.’ I spent time sitting on a couch, feeling OK, reading a book, pursuing friendships and not wanting to jump out the window. I spent a couple of years just trying to feel OK with myself and not always to be in a white-knuckle state of despair. And I succeeded. I felt my whole life up until that point had been swimming against the current. I came to realise what I was fighting for didn’t make sense any more.

But how does that impact on your creativity? If you’re felling OK and pretty contended with your life, does that make for good music?

I don’t remember particularly needing to be fucked up to write music. But I don’t remember not being fucked up when I was writing music. But by the end I couldn’t write a song because I was high and I felt like my head was stuffed full of cardboard. I had nothing interesting to say. And when I started this record, which was Jan 2004, it felt like there were a million ideas stuck in my head that were finally able to come out. I found I could pursue an idea down its course, whereas before I’d get two bends down the road and I’d forget what I was doing. It was so empowering to feel I could think again. It feels pretty good to be able to look at fresh experiences with a new clarity. Because I’d lost that. I’m not just trying to be the positive ex-junkie guy and I hate to be preachy. But what I’ve gained is so much more than what I’ve had to give up.

The album ‘Halo 19: With Teeth’ is out on Island on May 2.