MOSCOW -- President Mikhail S. Gorbachev has begun an aggressive, high-stakes campaign to persuade or bludgeon all 15 republics into signing the union treaty he has proposed in an attempt to prevent the disintegration of the Soviet Union.
Working simultaneously through the Communist Party, the army and the media, he is concentrating his efforts on the giant Russian Federation, where political rival Boris N. Yeltsin appears in no hurry to sign the treaty, and the Baltic republics, which have flatly refused to sign the treaty.
Yesterday, he managed to outmaneuver Mr. Yeltsin to get the union treaty on the agenda of the Russian Congress of People's Deputies and fired off two decrees aimed at protecting the Communist Party and the Soviet army from discrimination in the Baltic republics and elsewhere.
Both approaches appear risky for the Soviet president, putting his authority on the line in a confrontation with the far more popular Mr. Yeltsin and taking a chance on sparking violence between Baltic nationalists and Soviet troops.
But Mr. Gorbachev is in a fighting mood. He branded opponents of the treaty "demagogues" and said he was confident all the republics eventually will sign.
"Even those who are most vocal in condemning the treaty today won't be able to change anything," he told members of the Russian Congress.
Mr. Gorbachev dispatched Defense Minister Dmitry T. Yazov to speak on television last night with a stern warning to republican nationalists against attacks on the Soviet army, saying troops would use weapons to defend themselves and to guard supplies of water and power.
Alarmed by the heated rhetoric, the three Baltic republics decided to hold an emergency joint session of their parliaments in Vilnius, Lithuania, Saturday to discuss the threat of economic or military action. Estonia, Latvia and Lithuania, all occupied by Soviet troops in 1940, declared their independence from the Soviet Union last spring.
The two decrees Mr. Gorbachev issued yesterday both clearly targeted the Balts. The decrees:
* Declared void a Lithuanian law prohibiting military and law-enforcement personnel from joining political parties. The Lithuanian law was aimed at the Communist Party, whose relatively few remaining Moscow loyalists in Lithuania are leading the fight to keep the republic in the union.
* Ordered local officials everywhere to grant official residential permits to all Soviet military personnel and their families stationed on their territory. Officials in the Baltics and some other republics have refused such permits, which are necessary to buy food, find work and otherwise live normally.
A union is imaginable without the Baltic republics, whose total population is less than 10 million. But no union would be possible without the 150-million-strong Russian Federation.
Hence Mr. Gorbachev's rivalry with Mr. Yeltsin is developing into a struggle over the union treaty. While Mr. Yeltsin says Russia will eventually sign a treaty, he wants to dissolve much of the central bureaucracy and cut the central government's powers more than is foreseen in Mr. Gorbachev's plan.
Thus Mr. Yeltsin did not want the union treaty on the agenda, which is devoted mainly to the food problem, for fear the Congress might be panicked into approving Mr. Gorbachev's draft treaty unconditionally.
Monday, on the eve of yesterday's Congress opening, Mr. Gorbachev summoned the 600 Communist Party members in the 1,000-strong Congress. He told them they should fight to get the union treaty on the agenda.
So Communist deputies lined up at the microphones yesterday and virtually filibustered until Mr. Yeltsin agreed to a compromise: The deputies will "exchange opinions about the principles" of the union treaty without voting it up or down.