Mikhail Gorbachev comes to Washington in June 1990 the way Richard Nixon came to Moscow in June 1974: on the ropes. Like Nixon then, Gorbachev, severely wounded at home, is seeking succor in the adulation of foreigners. Like Nixon, too, Gorbachev is suffering a crisis of authority. Though Gorbachev has accumulated more institutional power than any Soviet leader since Stalin, his authority is such that not even the Moscow food shopper is taking him seriously.

For a long time American policy rightly centered upon the person of Mikhail Gorbachev because (1) he was doing the right thing (glasnost, letting Eastern Europe go), (2) he was in charge, and (3) there was no alternative. In the last few months, that has changed. Gorbachev has slowed both domestic reform and foreign policy accommodations with the West. He is rapidly losing control over the very forces that he has loosed in his country. And most important, a credible alternative to Gorbachev has finally emerged: Boris Yeltsin and the forces of democratic Russia.

Regardless of what happens at the summit, the most important event of the week -- the resurrection of Boris Yeltsin as president of the Russian republic -- has already occurred. Yeltsin is important first because he leads the forces of the democratic opposition. He has elaborated a genuinely social democratic program: real economic reform (restoring property rights, a shift to consumer goods), real political reform (breaking the power of the Communist Party) and real constitutional reform (negotiating a new covenant with dissatisfied republics: Yeltsin's first act as president of Russia was to announce that he would send a delegation to the Baltic states).

But Yeltsin is perhaps more important because he is the shrewdest, most popular politician in the Soviet Union. Yeltsin mastered the new political climate that Gorbachev created. As Gorbachev has grown more isolated, Yeltsin has acquired allies. He has, for example, skillfully aligned himself with the more liberal Russian nationalists, effectively taking the flag away from extremists like Pamyat. His popular support is the envy of Gorbachev.

Gorbachev has both a feud with Yeltsin and a well-based fear of his popularity. Gorbachev did everything he could to prevent Yeltsin's election, including a private pre-summit meeting with 400 hard-line deputies of the Russian parliament in which he called Yeltsin's supporters "parliamentary rabble."

The Bush administration's reaction to Yeltsin's election has been scandalous. It is one thing to respect Gorbachev. It is another slavishly to mimic his political prejudices. White House officials called Yeltsin an intellectual lightweight and a demagogue. Demagoguery is a charge that a read-my-lips presidency should use with circumspection. "Intellectual lightweight?" said Stephen Sestanovich. "Compared to whom? Compared to ... need I go on?"

Dumping on the first democratically elected leader of Russia because he casts a shadow on the summit and upsets our invited guest is taking politeness to an unseemly extreme. It is not just bad principles, it is bad politics. There may be a Yeltsin in our future.

I have long agreed with Timothy Garton Ash that "the worse alternatives {to Gorbachev} seem more likely to gain the upper hand than the better." Which was the reason to make Gorbachev the center of our foreign policy. But the crisis of Gorbachev's authority, illustrated by the economic panic in response to yet another half-measured "market" plan and now Yeltsin's accession to the Russian presidency, remakes the calculation.

Yesterday's formulas are already obsolete. It made sense to do everything we could to support Gorbachev when something worse -- some KGB or other neo-Stalinist strongman -- was the more likely alternative. But Yeltsin's victory indicates that now may indeed be the moment for something better. Perhaps the only moment. Moreover, given Gorbachev's weakness and the chaos that he has engendered, the status quo is untenable. If persisted in, it must give way to something worse.

The lesson of Poland is that only reformers with popular authority can survive, let alone reform. Perestroika is sinking because there is no chance of reform without a mandate, and Gorbachev does not have one. The Russian democrats do. They are riding a wave of popular support. There is now a historical window. Gorbachev can save himself and perestroika only with a liberal alliance.

If Gorbachev waits, economic and social conditions will get worse. A year or two more of Weimar Russia and the chance then of unreconstructed dictatorial elements taking over radically increases. (Whether Gorbachev or a replacement will get to play Deng is immaterial.)

As Dimitri Simes points out, Gorbachev may not be finished, but he is finished as a dictator. His choice is clear: either a clean break with the autocratic past and a clear move toward the liberals as represented by Yeltsin or an acceleration of his recent turn to the right and a future of repression and chaos. Gorbachev cannot stay put. The status quo will not hold. He must choose.

President Bush will have a lot to say to Gorbachev at the summit. But the most important thing that Bush can do is repeat to Gorbachev in the coziness of Camp David what he said to the world in his inaugural address: the day of the dictator is over. Your future is with the liberals. Embrace Yeltsin and the democratic forces. If you do, the outpouring of Western help, even Western concessions, will astonish you and benefit us both.