Field Marshal Lord Charles Guthrie of Craigiebank, 73, is Britain’s highest-ranking army general who was head of the country’s armed forces from 1997 until 2001, under the government of Tony Blair. He also happens to be a convert to Catholicism, received into the Church in his 40s.

Over the course of his career, Lord Guthrie has served in, among other countries, Malaysia, the Persian Gulf, the Balkans, East and West Africa and Northern Ireland. From 2000 until 2009, he was colonel commandant of the SAS, Britain’s special forces; and in June this year, Queen Elizabeth II raised him to the rank of field marshal.

Speaking to the Register at his residence in London July 20, Lord Guthrie discusses his conversion, the effect his faith has had on him as a soldier, the just-war tradition and a number of contentious debates and topical issues.

What drew you to the Catholic Church, and how did your conversion begin?

Well, it didn’t happen like Saul on the road to Damascus. It took quite a long time. My father had become a Catholic when he was 68, and we were always that way inclined. We went to church and all that, and it seemed to me that I would probably end up there.

Was your mother Catholic as well?

No. Gradually, it got more and more obvious I should be a Catholic. I was influenced by various priests I knew, various army chaplains I knew. I was influenced by my wife. But I always think I’d probably have been a Catholic more quickly if I hadn’t been married to her.

She really is a good Catholic who does an awful lot of things for the Church, but the reason I say that is because I wanted to be absolutely sure that I did want to be a Catholic not just because it was convenient to be a Catholic — you know, with only one car, who’s going to have it on Sunday, that sort of thing.

I also was a general in Yorkshire, very near to Ampleforth [Benedictine] Abbey, and I had a great friend, who’s still a great friend of mine, who’s a monk there and three or four people who really influenced me.

What aspect of the faith was it that drew you?

Obviously, the Church does an awful lot of good, looking after the poor and the sick. But that wasn’t the reason. It was more of the spiritual side which drew me to the Church, and l look upon the work that people do as rather an extra, really.

You can’t become a Catholic because there are a lot of poor people sleeping outside Westminster Cathedral. You’ve got to have a better reason than that.

Was there anything in your work as a general that the faith brought to you — a certain solace or peace?

Yes, it was hugely helpful. It gave you a spiritual, moral and ethical background, and maybe a confidence which you may not have had otherwise. But being in the military is not easy because you do have to make some terrible decisions sometimes, though not always. But you know, if you don’t like it, don’t join, and I certainly have no regrets about it.

How do you reconcile your faith with being a soldier?

Absolutely no problem at all. I think it’s a great help to have a faith if you’re a soldier. You’re very fortunate to have this sort of moral background on which to build your views. You’ll find that in a battle there are very few people who aren’t religious when you’re frightened. I’ve noticed that — very much so. The numbers who go and see their priest usually rise quite considerably.

Did you have occasions when you had to carry out orders that went against your conscience?

No, I can’t think of any. I was always comfortable with the reasons I was doing something. I never found myself in Malaysia, Borneo, East Africa, West Africa or Northern Ireland where I was morally affronted by what I was being asked to do. Of course, there are always people — and these things happen — who do behave badly. But you must stop that. That’s why human-rights courts and the law [is] a good thing.

If people do misbehave, start torturing captured soldiers or families, that’s very wrong.

What is your general view on torture?

My view is absolutely clear, which is that torture is wrong and shouldn’t be allowed, and people who torture should be apprehended, with the full force of law applied.

It does huge harm. I also think that torture — and I include waterboarding in torture — almost always does far more harm than good. Just think how many moderate Muslims have been shocked by what has gone on in Abu Ghraib, Bagram and Guantanamo by people waterboarding and this nation of the United States, in particular, which has stood up for human rights and seen to be doing it.

I think that is very damaging. I also think that people tend to tell you what you want to hear when being tortured.

You have written a book on the just-war tradition (Just War — The Just War Tradition: Ethics in Modern Warfare by Charles Guthrie and Michael Quinlan, Bloomsbury, 2007). How applicable is it, given that it can be open to such diverse interpretations?

The tradition has been worked out over thousands of years, really. Every nation really has had to come to terms with kinds of [just war] tradition.

Among the ancient Greeks in the ancient world, you weren’t allowed to poison wells, you weren’t allowed to cut down olive trees, and you weren’t allowed to kill women and children. That doesn’t mean those things weren’t allowed sometimes to happen. People do behave very badly in armed conflict sometimes, but it does seem to me to be absolutely right that you have a moral compass which sets standards.

There are certain parts of the tradition you really do have to think very, very carefully about before you move away from them. First of all, you have to have a very good reason to go to war. It’s not good enough just because you want to punish somebody or revenge. You’ve got actually think: What are the consequences going to be? Are you going to make things better?

You really have got to have a very good reason. War is a horrible thing, a disastrous thing, but sometimes there are things which are even worse, like genocide, the completely uncontrolled killing of innocent women and children.

Some people will say, "Well, war is evil." Well, of course, it is evil. But there are worse things. … What do you do if barbarians are at the gate, and you know they’re going to kill everybody who’s sheltering in your town? Would you let them do it, and kill everybody in their path, which some of them used to do?

Well, I think the answer is: You certainly shouldn’t do that. And that’s why under certain circumstances you do need to go to war; you do need to take action.

What do you say to the argument that as Christians we are called to be martyrs if necessary, that that is how we should resist?

I think it’s crazy. If you had Attila the Hun coming, and you had a country of 100,000 people, do you think it’s a good idea to stand by and watch 100,000 people killed? That doesn’t make any sense at all in the real world. I’m very suspicious of that. It just doesn’t work, never has worked, and I don’t see why it should. But you don’t want to go to war; you want to think very, very carefully about what it actually means.

What about bringing civilization to people as a reason?

Bringing civilization is of course a marvelous idea, but you shouldn’t think you’re going to do that very quickly.

And yet, as Robespierre said, no one likes armed missionaries.

No one likes to do it, but you come to the question of last resort. What does last resort mean? Does it mean don’t take action as someone is going to cut your throat and is on top of you and doing it? Last resort means, I think, the last sensible thing.

It always struck me as a bit odd that you had a series of things that you must do to see if it will stop a war. But there’s no point dropping leaflets on somebody who is just about to kill you or blow you up. You’ve left it a bit late then. So that’s not the last resort; the last resort must be pre-emptive. And pre-emption is an extremely difficult subject because weapons are very destructive and can be launched from far away.

There’s this argument about the United States and Israel now. I think a pre-emptive strike would be completely wrong for Israel or for anyone to do against the Iranians at the moment. On the other hand, in the Six-Day War, the Israelis had something on their side because the Arab armies had surrounded Israel, and Israel is an extremely difficult country to defend. It’s very narrow.

Once you let them cross into Israel, the game was lost, as far as the Israelis were concerned. But there are other reasons: Are you going to make things worse? I think that it was absolutely right to go to the first Iraq War because Saddam Hussein was destroying a country and committing genocide against the Kuwaitis.

So I think it was quite right that the United Nations took action. But there’s no point in taking action unless you’re actually going to achieve your goal, and that’s a difficult thing. I can think of only one war of a country that had declared war and started it knowing it was going to lose, but probably did better for going to war, and that was Finland against Russia. But there are not many wars I can think of like that.

Is it possible to fight a just war, given that some military theorists have said you must use maximum force, or absolute war, to win an armed conflict?

You want to get the war over as quickly as possible. You don’t want to kill any more people than you have to, and you want to protect people who are not actively engaged in the war, like women and children and non-combatants.

But what is a non-combatant? When are people engaged in war? Is, for instance, somebody working in a munitions factory? Civilians supplying troops in the front line? Well they are engaged. Are broadcasters producing propaganda to help the enemy? They are engaged, but it’s quite a tricky thing to say they ought to be killed or arrested or stopped.

You get into very difficult areas; these things aren’t black and white at all.

Was the allied bombing of Dresden in the Second World War, for example, therefore unjust?

Dresden will always be very controversial. I think nowadays more and more of us think it wasn’t right because we were winning the war anyhow. But if you had been involved, you might take a rather different view; and I think it would be very wrong of us to condemn everybody who was involved.

But at the moment, with Dresden, I would think that you probably wouldn’t do it if you had all the evidence. Hamburg was very bad, too. But on the other hand, there was the bombing of London — 60,000 people killed here, and they were civilians. Some may have been munitions workers, but there were very few.

But when something like Dresden happens, does it make a war unjust, according to the just-war principle of jus in bello — the law limiting acceptable wartime conduct?

It’s how you behave in a war. I don’t say it makes it unjust. It’s a very difficult question because you can’t say: "We’ve done this, and so it’s unjust." There’s not a sliding scale of what’s just or unjust. But it goes back to what I said: You don’t begin unless you think it’s just. You don’t want to create the sort of atmospherics to go to war. You’ve got to be sure you’re not making things worse, but that you have a plan after the war is over.

Did the Americans have a plan after the first Iraq War? No, not really. They felt that by hitting Saddam Hussein hard everything would collapse.

Is the current war in Afghanistan a just and worthy conflict, in your view?

I do have a problem with Afghanistan, and that is that people didn’t really think of the consequences.

My own view is that there’s absolutely no question over whether it’s perfectly lawful, perfectly morally right, for the special forces in our countries, particularly the SAS, the SBS and the American equivalents, to go and destroy the Al Qaeda camps. … It was quite right that we did that, and I think that was achieved brilliantly.

I would then question — and we come to unforeseen consequences again — should we not have just come home then?

We [then] got involved in all sorts of laudable things: destroying the poppy crop, trying to impose democracy, women’s rights, a whole raft of things which were actually beyond us unless we were going to make a far, far bigger effort than we did.

You could argue that we did make things a bit worse, and we did one thing which people forget, which is that the Taliban were not really our enemies to start with. Al Qaeda was, and the Taliban just hated the thought of us being in the country.

The second thing, really, is using massive force unnecessarily and wrongly. Clearly, you don’t want to kill masses of people. I don’t think you do anyhow. But if, for instance, you have a tank shooting at you, and you need to destroy it, well, there are certain circumstances when you should destroy it. But if that tank is hiding in a hospital or in a school or in a civilian community, it seems to be me to be absolutely wrong to destroy the whole school and civilian community and get the tank as well. It would be wrong, but none of these things are very easy, because you have to make very quick decisions sometimes on incomplete evidence.

What is your opinion on the use of drones?

In actual fact, I think that a lot of nonsense is talked about drones — that they’re unfair. Well, I think that there is human error sometimes, and drones do sometimes go wrong. There is a sort of British thing: that it’s not really cricket to kill people if they haven’t got a chance to kill you. … Now, it’s very, very regrettable that people get killed, the wrong people sometimes, which is why you’ve got to be so, so careful. I don’t know, really know, about some of the things you hear going on with American drones in Pakistan, and I review the reporting of these subjects with some suspicion.

All I do know is that very large numbers of Al Qaeda have been removed and that the situation is probably better. I haven’t got enough evidence about it.

Proponents say the casualties are less.

Well, that’s what you hope, and if you can bring the war to a quicker end, and then be prepared to do something about it. I think what you can’t do is just win a war and then go away. That would be very wrong, quite honestly.

What are your views on the Israeli-Palestinian conflict?

Both sides are right, and both sides are wrong. It’s an astonishingly difficult [conflict]. I think a lot of people take sides without really understanding what the problem is.

I’m amazed how I hear diplomats either being pro one side or the other. There’s a huge problem; we want to help. Israel is a fact. It’s a country with many people living in it, and both the United Nations and I believe, for instance, it has a right to be there. … It’s very difficult to impose peace and make people love each other. And it’s very difficult to impose a united force on a warring faction that’s going on.

Would you advocate intervention in Syria?

Certainly, not at the moment I wouldn’t, because I think it would make things worse. Syria is a huge country. I don’t know enough about it, [but] who would want to go to Syria? Russia certainly wouldn’t; the Chinese wouldn’t. It would make America even more unpopular and make it [Syria] very unstable. It’s a very dangerous region.

It’s not like the NATO intervention in Libya?

It’s not like Libya. That was relatively easy, but we haven’t heard the last of what’s going on [there]. That’s the difficulty with the unforeseen consequences [of war]: You quite often don’t know. War is not like a folio of a play, when you know what the ending is, and you know what the characters are.

The enemy nearly always does something you don’t want him to do and doesn’t react in the way you would like him to react, and I’ve seen that time and time again.

Would you consider yourself an interventionist?

Well, I’m an interventionist on some things, if you know what you’re doing. When I was chief of the General Staff [head of the British army], various ministers wanted us to intervene in something we really couldn’t have done. It’s important for people like me to tell them they can’t do it. But, on the other hand, Sierra Leone is a very good case [British forces helped end a 10-year civil war there in the late 1990s]. The British did magnificently there.

Were you in charge then of the armed forces?

Yes, and the U.N. were not doing well; they were slightly arguing among themselves. I had a great discussion with the prime minister: that even if the U.N. approved of the operation, I didn’t want the British put under the command of the U.N.; so we weren’t. The U.N. were a bit upset about that.

Was that the secret of its success?

In many ways, yes. The chain of command is dead easy.

Edward Pentin writes from Rome.