Despite all the predictions that NATO expansion would sail through the Senate like a slam-dunk, the Senate is likely to adjourn this week without a ratification vote. True, the delay is largely due to the refusal by the majority leader, Trent Lott, to let NATO expansion come up for a vote while Democrats were filibustering a Republican education bill. But it is also true that the more the Senate debates the NATO issue, the more senators actually focus on it, and the more they ask the central question to which the Clinton team has never given a satisfactory answer: "Why are we doing this now?"

Senators, you're not alone. Why are we doing this now?If you ask conservative supporters of NATO expansion, they are at least honest about their ends. They want to expand NATO because they are anti-Russian and they want to contain Russia every bit as much as they wanted to contain the Soviet Union. For them, there is no real difference. The conservatives believe that the United States won the Cold War and is entitled to reap the fruits, which means expanding NATO all the way from its present borders up to the Russian border, including the three Baltic States: Latvia, Lithuania and Estonia.

Personally, I thought we fought the Cold War not to contain Russia but to change Russia - so Moscow could really work with the United States in reducing both countries' nuclear arsenals, stemming weapons proliferation and confronting rogue states. I thought the real fruit of the Cold War would be to have a Russia that cooperates with us on our post-Cold War agenda. That would require investing in Russian democracy. But conservatives would rather enjoy the psychic pleasure of having the Czechs in NATO, rather than the real advantages that could come from a transformed Russia.

But where conservatives are not being straightforward is about their means. They want NATO to go all the way to the Baltic-Russian border, but America's European allies are dead against that, because they know it would be a provocation to Moscow.

As for the liberal expansionists, they are dishonest about their ends and their means. NATO expansion isn't anti-Russian, they aver. The alliance is being expanded simply to consolidate democracy in Europe and to enable NATO to better confront post-Cold War threats. Oh, really? You mean like Saddam Hussein? He's the epitome of the new post-Cold War, and when it came time to confront him, one NATO ally - one - Britain, was ready to fight with the United States. The others sent nurses and gas masks. Thanks a lot.

"NATO expansion is the equivalent of the Gulf of Tonkin Resolution that authorized the war in Vietnam," says the Johns Hopkins foreign policy expert Michael Mandelbaum. "Like that commitment to Vietnam, if NATO expansion is launched we will be unable to go backward, because we can't expel these countries; unable to go forward, because the Europeans are not ready to expand NATO to the Russian border; and unable to stay where we are, because we have vowed to expand NATO to the Russian border and not to do so would be to draw a new dividing line in Europe."

One can only hope that more senators will see this too. Because if they vote for NATO expansion, there is no bridge to cross later, there is no cost-free rest stop along the way. There is only a car with no brakes on a slippery slope to trouble.

New York Times News Service