WE do not pretend that we find it easy to wrestle with the momentous dilemma over Britain's future as a nuclear power.

It is a huge issue, with impassioned views on both sides, and it is far from being black and white.

It is an uncertain world and that is extremely unlikely to change. The threats to world peace are constantly evolving and becoming more complex.

But, while it may be naïve and idealistic, we also find it inconceivable that we should give up hope of entering into international agreements which slow down the spread of nuclear weapons.

The next point at which that hope comes alive is when the Non-Proliferation Treaty is renegotiated in 2010.

If we take the binding decision in 2007 to spend £20bn on the new Trident, it will be very difficult for our negotiators to go in to the conference in three years' time and suggest that other countries slow down in the nuclear arms race because we will be actively surging forward ourselves.

We will be calling for the brakes to be applied while ramming down the accelerator. Just as we are urging the United Nations to thwart Iran's nuclear ambitions, there is clear irony in the fact that we are so hastily pressing ahead with the next generation of our nuclear ambitions.

There will never be a good time to make this unenviable decision. But while we are convinced of the need to remain stoutly defended, we find it hard to come to terms with the hypocrisy of pressing ahead with a replacement for Trident so close to crucial international dialogue aimed at finding some sense amid the madness.