Ten years ago, on December 5 1994, the first Strategic Arms Reduction Treaty entered into force. Today, with the cold war behind us, the chances of a premeditated, deliberate nuclear attack have fallen dramatically. We know that. But we should also know that the chances of an accidental, mistaken or unauthorised nuclear attack might be increasing.
There are several causes: budget problems and an erosion in non-nuclear forces in Russia have led the military to increase its reliance on nuclear weapons; a tilt in the US and Russian strategic forces in favour of the US makes Russia more likely to launch upon warning of an attack, without waiting to see if the warning is accurate; and the Russian early warning system is in serious disrepair and more likely to give a false warning of incoming missiles.
America's survival could depend on the accuracy of Russia's warning systems and its command and control - an absurd situation for both nations.
There is another danger, which compounds the risk of all three: the high-alert, hair- trigger nuclear posture in both countries, which allows missiles to be launched within minutes. This hair-trigger capability would force our leaders to decide almost instantly whether to launch nuclear weapons once they have warning of an attack, robbing them of the time they may need to gather data, exchange information, gain perspective, discover an error and avoid a catastrophic mistake.
President Bush has long understood the danger. In the summer of 2000, in a speech entitled "New Leadership on National Security", candidate Bush said: "The United States should remove as many weapons as possible from high-alert, hair-trigger status - another unnecessary vestige of cold war confrontation . . . . Today, for two nations at peace, keeping so many weapons on high alert may create unacceptable risks of accidental or unauthorised launch. So, as president, I will ask for an assessment of what we can safely do to lower the alert status of our forces."
More than five years later, and 15 years after the end of the cold war, we continue to run these same "unacceptable risks". The Treaty of Moscow that Presidents Bush and Putin signed in 2002 did nothing to specifically address hair-trigger status, which in my view is the most dangerous element of the US and Russian force postures.
Keeping our nuclear weapons on hair-trigger now increases, for both nations, the risk it was designed to reduce. It is high time to find a safer form of deterrence and security. The burden of leadership falls squarely on the US and Russia. Our two presidents should eliminate this dangerous cold war legacy by making a joint commitment that would include three parts.
First, both countries should commit to a process to remove all US and Russian nuclear weapons from hair-trigger alert. This would allow more time to think before launching - first adding hours and then days.
Second, as an intermediate step, the US and Russia should reduce the number of warheads on hair-trigger alert from several thousand to several hundred.
Third, the US and Russia should engage in a dialogue with other nuclear weapon states to de-emphasise globally the importance of nuclear weapons and gain mutual assurances that no state will, in the absence of an imminent threat, deploy its nuclear weapons on hair-trigger status.
These steps should be taken in concert with a broader presidential directive to further define and reduce the role of nuclear weapons in our national security strategy.
If the US and Russia remove all nuclear weapons from hair-trigger status while maintaining smaller but survivable forces, we can reduce the danger we pose to each other. By reducing our reliance on nuclear weapons, the US and Russia will also gain the credibility now missing to get others to join in applying pressure on nations still seeking nuclear arms, and to rally the world to secure all weapons grade nuclear materials, greatly reducing the risk of catastrophic terrorism.
For far too long, we have let the nuclear legacy of the cold war linger. In doing so, we are running an unnecessary risk of an Armageddon of our own making. If it happens, God forbid, our epitaph will read like the decline of other species: "Too slow in adapting to a changing environment."
The writer, a former chairman of the US Senate Armed Services Committee, is co- chairman of the Nuclear Threat Initiative.
In an op-ed published in The Financial Times, Sam Nunn discusses U.S. and Russian nuclear postures.