These are the men who would have to push the button if America ever went to nuclear war.

BBC Washington Correspondent Tom Carver: Why America wants the bomb

From their subterranean shelter they can fire off ten Minuteman missiles, each with three atomic warheads, in a matter of minutes.

The army insists that an accidental launch is impossible as the soldiers cannot activate the system unless they are given a secret firing code by the president.

Atomic arsenal under attack

Despite these assurances, some former advocates of the nuclear deterrent question whether in the post-Cold War era it is really necessary or safe to have thousands of warheads in a state of constant readiness.

The button cannot be pressed without the president's code

Some have joined the bands of nuclear campaigners who have long called for partial or total disarmament.

Bruce Blair, a former Minuteman battery commander, says that Russia's nuclear stockpile is in such a dangerous state of disrepair that there is a serious risk of an accidental launch which could lead to swift retaliation by the US.

"We currently have thousands of strategic weapons poised for immediate launch on both sides," says Mr Blair, now an arms analyst with the independent research organisation the Brookings Institution.

"It's excessive from the standpoint of deterrents, and it's excessive from the standpoint of the risk of their mistaken or inadvertent use," he adds.

New nuclear nations

But Russia is no longer the only other country in the atomic equation.

This year new nuclear powers have appeared on the scene in the shape of India and Pakistan. Both countries have suffered American economic sanctions for holding missile tests. But they have countered by accusing the US of hypocrisy for lecturing them when it retains a vast nuclear arsenal.

A missile silo

International disarmament agreements are poised to slash the number of American warheads by two thirds over the next few years.

However, President Clinton's key advisor on nuclear issues, Bob Bell believes that America must hold on to some nuclear weapons in order to make rogue states think twice before attacking the US.