MOSCOW -- If nostalgia enveloped George Bush on his 25th and probably final foreign adventure as president, there was also some nostalgia for the old sureties of traditional arms control.
The second Strategic Arms Reduction Treaty, known as START II, given its very sweep, is likely to be the last agreement of its kind. It represents both the triumph and the limit of bilateral negotiations on arms control in a world that is no longer bipolar.
The Soviet Union may have been a totalitarian menace, but its military commanders -- especially in comparison with the military commanders in some of the world's current trouble spots -- were responsible professionals who knew the dangers of the weapons they brandished or faced, and who could largely be expected to keep to the letter of the agreements they signed, however long or hard the negotiation.
There was no fuss then about ratification by parliaments or any need to assuage the wounded pride of new states, like Ukraine, that woke up as nuclear powers and started to like the way it looked in the mirror.
Each difficult, incremental treaty on the road to START II felt momentous -- not because arms were reduced in any meaningful way, but because the gap of ideology and misperceptions crossed by the superpowers was so cavernous and the rope across it seemed so thin.
The treaty is a legitimately momentous agreement, around which President Bush, President Boris N. Yeltsin and their speech writers did their best to spin flourishes of oratory about peace, children, trust and brotherhood. But there was a curious lack of moment.
In part, this fact was caused by the haste of negotiation, and in part by Russia's impoverished condition, as an imploded empire reaching for aid and acceptance. Russia's diminished status seemed to intensify Mr. Bush's, as a lame-duck president who kept checking his watch when he wasn't checking his tears.
But there is a deep, underlying sense that the new world is not only more complicated, but also considerably more volatile than the old.
The end of the Cold War straitjacket has meant the start of conflicts based on old nationalisms and economic rivalries, just as the collapse of the old fears of mutual assured destruction and nuclear holocaust has made the world safe for conventional war.
As much as Mr. Bush and Mr. Yeltsin talked of cooperation and partnership, they clearly have their disagreements over how to deal with Serbian aggression in the former Yugoslavia. Russian conservatives and some nationalists say they feel that Mr. Yeltsin has already betrayed their "Serbian brethren," let alone old Soviet allies in Iraq, Syria, Cuba and elsewhere.
The shelling over Mogadishu, Somalia, while Mr. Bush spent Friday night on a U.S. naval vessel offshore, was a reminder of the limits of relief intervention and feel-good gestures that Russian-U.S. amity cannot solve.
In Cambodia, where Washington and Moscow brokered a peace treaty through the U.N. Security Council, the Khmer Rouge's blatant defiance of that treaty and their continual kidnapping of U.N. peacekeeping troops promises a future renewal of horrors that could make Serbian behavior seem civilized.
Senior U.S. officials here spoke of the future tasks of arms control, pointing to the Chemical Weapons Convention, scheduled to be signed shortly in Paris, and the effort to extend the Nuclear Nonproliferation Treaty beyond 1995.
But they also understand how difficult START II will be to ratify and carry out, even assuming that Ukraine, Belarus and Kazakhstan follow through on their pledges to become non-nuclear states.
According to a study by the John F. Kennedy School of Government at Harvard, the U.S. and Russian side each employs over a million people to build, field and maintain its nuclear arsenal. Dismantling these structures will present fundamental political, economic and environmental problems. Dismantling the weapons themselves, plus thousands of tactical nuclear weapons, is full of dangers.
The Harvard study estimates that the Russians will have to destroy 100,000 metric tons of liquid rocket propellant, which explodes on contact with air, let alone safely transport, store and protect the highly prized nuclear material in all those warheads.
Washington has promised direct financial and technical aid to Moscow and Kiev for these purposes, but the cost of dismantling these arsenals in safety is likely to be shocking, diplomats suggest, far in excess of the initial U.S. installment of $800 million.
One senior U.S. official said wanly that "democracy is the best form of arms control," arguing that democratic nations do not start wars.
But it is always possible, as Foreign Minister Andrei V. Kozyrev of Russia made clear last month in his stunning mock speech in Stockholm, that the Russian government may one day end up in the hands of extreme nationalist, anti-Western politicians or military men who will treat START II much as President Saddam Hussein of Iraq treated his solemn commitments.
Another U.S. official cautioned that there were limits to Washington's ability to influence events here or even to control how Russia carries out the treaty signed with so much hope here yesterday.
"Both the financial obligations and the willingness to undertake the task are responsibilities that Russia and the other parties are accepting themselves," he said.
"It is the Russian people and their leadership in this present instance who want to put some of the worst and most destabilizing aspects of the nuclear age behind us and accept that responsibility. We can help, but we're by no means the principal actor."