Love Conquers All : U.S.-Soviet Relations: When an American political blueblood can meet, not to mention marry, a Russian of space-wars eminence, we know <i> glasnost </i> is working.

On Wednesday, the Central Committee of the Communist Party decided to give up its constitutional guarantee of power over the Soviet Union. On Friday, two friends of mine got married in Moscow. It is hard to say which event better captures the essence of the times.

The bride runs a Washington public-relations firm, specializing in Soviet affairs; the bridegroom is a physicist, from my own profession. Pravda announced the engagement, and President Bush invited the couple to the White House for an engagement dinner.

No ordinary couple, clearly. She is Susan Eisenhower, the granddaughter of the U.S. President who presided over much of the early Cold War. He is Roald Z. Sagdeev, once the head of the Soviet space-science program and a member of the old Supreme Soviet from Odessa, now a representative to the Congress of People’s Deputies.

For two people from such different worlds to meet would have been, at the least, improbable just a few years ago. Soviet space research was conducted in private until success was achieved; Roald was known to the physics community as a brilliant scientist and organizer--and one of the honest brokers within the Soviet arms-control Establishment--but he had little contact with press and public. Susan was trying to bootstrap a small business while also running the Eisenhower World Affairs Institute established in memory of her grandfather. There was no logical place for their paths to cross.

With the advent of the Gorbachev liberalization and glasnost, however, both found themselves invited to a Chautauqua meeting to discuss Soviet-American relations. Both next landed on the board of directors of a Soviet-American foundation established to promote peace. Human-rights discussions turned to human relations; sometime a year or so ago, romance broke out.

But consider the problems of such a romance, not as we see them today but as they would have appeared in, say, 1986--not so very long ago--a year before Susan and Roald met. If a prominent American Republican, the bearer of one of the most honored names in our history, chose to marry a Soviet citizen, she would have been called disloyal at best, and surely not invited to celebrate at the White House. For a Soviet citizen, a scientist, politician and member of the kitchen cabinet of the General Secretary, marriage to an American would have meant immediate expulsion from all of his positions of power and exclusion from his profession.

Even the questions of where to live and how to make a living would have seemed impossible to resolve. Soviet spouses of Americans were usually refused permission to emigrate; the American spouses were rarely allowed into the Soviet Union to visit. Susan and Roald will divide their time between Washington and Moscow. Each has been assured that travel will be no problem.

It is probably easier for a famous couple to make a Soviet-American marriage work; both know how to cut through their countries’ overloaded bureaucracies, and their fame may provide a certain shield. Even so, it cannot have appeared easy when they first fell in love.

Undoubtedly many institutions will compete to provide an American base for Sagdeev’s research in science and arms control. We have always welcomed eminent defectors, but Roald Sagdeev is no defector. He will shuttle between IKI, the Soviet space-science institute where he was once director, and whatever U.S. institution he chooses. And he will return to the Soviet Parliament better informed about American life and politics than any other legislator in the short history of Soviet open government. He has always been a leader in the reform movement in his own country; we can hope that his superior knowledge of the United States will help him further the goals of his late friend and colleague, Andrei Sakharov.

And it will be no bad thing for President Bush to have a friend who lives in Moscow, and who can convey an accurate and first-hand impression of life there. Diplomatic reporting is essential to our understanding of Soviet affairs, but a friendly back channel to someone who gets her mail at a Russian address may provide insights available in no other way.

George Bush is clearly skeptical about the depth and the permanence of the reforms that Mikhail Gorbachev has forced upon the Soviet Union, and perhaps with good reason. Nevertheless, two intelligent and well-informed people have decided to bet everything they have that the Soviet Union of Cold War days has changed for good. Their confidence may be an even better omen than Gorbachev’s big win in the Central Committee. May their marriage be long and happy!