US/RUSSIA: Treaty a diplomatic coup for Mr Bush writes Patrick Smyth, Washington Correspondent
The dramatic announcement of strategic nuclear warhead cuts by Russia and the US was always going to be the easy bit of the nuclear arms equation.
While the debate about defensive capabilities remains deeply controversial, the extraordinary firepower of both countries, capable mutually of annihilating each other many times over, always meant there was room for manoeuvre in the reduction of offensive capabilities.
For Russia, unable to pay for the maintenance of its between 5,000 and 6,000 warheads, and the US, turning its focus to an alternative form of deterrence, the cuts were logical once the Cold War was over. The detail of decommissioning can be a finicky business.
While the Americans wanted to put their surplus missiles into bunkers for possible future use, in "emergencies", the Russians were keen to eliminate them altogether.
Yesterday's compromise announcement that the US will be able to store some of its weapons while destroying others thus takes us another on another logical step down the road that Mr Mikhail Gorbachev launched 10 years ago and which saw its expression in the START II treaty in which warhead numbers were due to fall in ten years to between 3,000 and 3,500. In 1997, Presidents Clinton and Yeltsin went further and agreed in principle that a START III treaty should cut numbers to 2,000 to 2,500.
Mr Bush fought an election campaign in which the modernisation of the US strategic arsenal while the US also researched a new generation of weapons and delivery systems, was a key part of a wholesale transformation of the military, and a natural corollary of his deeply controversial national missile defence proposals.
Last summer, Presidents Bush and Putin met in Genoa and agreed to go further still.
In Texas in November they signed up to the 1,700 to 2,200 nuclear weapon ceilings that will now be enshrined in the treaty.
Importantly for domestic approval in Russia, the deal leaves it with a capability that would, however, easily be sufficient to overwhelm whatever nuclear missile shield system the US develops.
The US programme, which has necessitated the US repudiation of the Anti-Ballistic Missile Treaty (ABM), is proceeding apace. Its rationale is being sold by the Americans as a system geared only to defending against limited attacks from rogue states and, in theory, not affecting the strategic balance between the US and the major nuclear powers. This is not a theory China or Russia accepts.
In this important respect the announcement reflects both an apparent continuity in policy and discontinuity.
The approach of the Americans is based on a new philosophy of deterrence in which the old "mutually assured destruction" (MAD) doctrine which underpinned Cold War deterrence is deemed inadequate to deal with irrational rogue states whose leaders are prepared to behave like suicide bombers.
"Deployment of effective missile defences may dissuade others from spending to obtain ballistic missiles, because missiles will not provide them what they want: the power to hold US and allied cities hostage to nuclear blackmail," the Secretary of Defence, Mr Donald Rumsfeld, argues in the latest issue of Foreign Affairs.
That the Russians should sign up to a cut in offensive weapons at this time represents an important diplomatic coup for an administration determined to answer its international critics's arguments that it is essentially unilateralist in its approach to such issues.
That's the downside. The upside is that we can all breathe a little easier.