STRATEGIC DIALOGUE between the two great nuclear powers, the United States and Russia, is coming down to the flexing of real and imagined missiles. The other day the Russians fired off a short-range interceptor missile -- a possible hint of a more ambitious shield to come. On any given day, its American advocates are urging a program to go beyond limited "theater" missile defense and to organize a full national missile defense.

Here lies one of the paramount, and most neglected, issues of American security policy. Americans insist the new program would be intended to defend just against rogue-state and terrorist missiles. But Russians see it as the core of a program that could overwhelm their own missile-defense forces. This is why Moscow opposes American-sought changes in the 1972 antiballistic missile (ABM) treaty -- changes that would propel the United States down a broad missile-defense path. The same basic considerations extend to Beijing as well.

There is real harm in these rhetorical and symbolic exchanges. They ignore the considerations of greatest psychological and political weight on each side. The United States, which has committed itself to the seeking of global stability, thereby needs a missile defense to stand up to rogues wherever they may be. To treat the new Russia the way Washington treated the old Soviet Union, as the single nuclear threat, will no longer do. Russia now is in a stage of acute internal shock. Its insecurities must be respected. This means that a new American national missile defense must not tread on Russia's legitimate fear for the integrity of its deterrent. It is the kind of project that urgently needs to be handed off to the negotiators.

What retards negotiation, on the American side anyway, is unusually fierce partisanship in Congress. A strong clique there sees a chance not merely to frustrate President Clinton's strategy but to undo the whole Cold War structure of arms control agreements and inspection procedures and to substitute for it a doctrine of defending America chiefly by unilateral applications of American power. This is largely a matter of faith, not logic, for those who feel that way. But there is a constituency available to support it, mostly in the Republican Party.

A careful revision of the anti-missile treaty can open the way to the sort of missile defense that makes nuclear sense and that contributes to an improved relationship with Russia. A curvy line can be drawn to ensure the United States of the missile defense it needs to conduct a global policy and to ensure Russia of the security and respect it needs while it is convalescing from calamitous systemic breakdown. It may not be too late for President Clinton to manage a diplomatic attack on these lines.