Sitting on an abandoned London tube station listening to a concert of modern classical music last Friday night, amid the dust, I thought of war.

I thought of the huddled men, women, and children who had sat on this same platform seven decades ago in a bid to escape the Blitz above.

And then I thought of now – what President Obama has called this era of “perpetual war”. War, not at home, but abroad. Two wars of choice, in Iraq and Afghanistan, and the overspill that finds UK troops and agents overtly or covertly present from Yemen to Pakistan, from Mali, to the fringes of Syria.

On Sunday I found myself returning to thinking about war at the wondrously warless Hay Festival. I had the honour of hosting and interviewing the former UN Chief Weapons Inspector Dr Han Blix.

Around 1,600 people packed in to hear Dr Blix deliver what proved to be political dynamite. His answers to questions the more so.

Dr Blix is speaking his mind and his strong and vibrant heart. At 84, he is seemingly unchanged from the man in his seventies whom I accompanied on some of his searches for WMD in Iraq.

If Britain and America had listened to this man, we would never have invaded and dismantled Iraq. Dr Blix talks with huge experience and authority about nuclear weapons.

‘Pointless exercise’

His most explosive statements centred on Britain’s plan, in an age of austerity, to spend vast billions on replacing Trident with a new “nuclear deterrent”. From a peace and security perspective he described it as “a completely pointless exercise”.

When we were talking back-stage, he had suggested to me that perhaps the British public would be very reluctant to abandon our nuclear weapon. I responded that I did not think public opinion on the matter had ever been seriously tested and that if it was, it would be very difficult to predict the outcome.

In the aftermath of the Hiroshima and Nagasaki nuclear massacres, the 1950s saw the rise of the “ban the bomb” movement. Today, all these years on, the “threat” is altogether different, as Dr Blix explained. Asymmetric warfare has no nuclear component. Even if it did it would be very hard to combat with a nuclear bomb.

Then he delivered his own “bomb”, calling upon Britain in most specific terms, to “abandon Trident altogether”. Indeed, to go further and abandon the bomb.

Next month the Whitehall review will endorse the continued costly replacement of Trident and rededicate the UK to a submarine-based nuclear weapons system.

It is hard to imagine that such a decision will kindle any kind of movement that could halt such a development. Welcome to the new nuclear generation – man the cash tills!

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