RESPONDING to President Bush's challenge to "make this a safer world," President Mikhail Gorbachev unveiled his own blueprint for arms control Saturday.Mr. Gorbachev announced "reciprocal radical measures leading to the elimination of tactical weapons." (See box, Page 3). He also called for "the earliest possible ratification of the treaty on strategic offensive weapons," and proposed further radical cuts in these arms, by as much as 50 percent. This issue, he said, will be discussed by the first session of the Supreme Soviet of New Convocation. The Supreme Soviet, originally scheduled for tomorrow, has been delayed until Oct. 21 because of power struggles between the Moscow center and the republics. Gorbachev promised to draw up plans for production of a small mobile strategic missile, as well as other nuclear modernization. He emphasized that, in addition to proposed US and Soviet disarmament, the other major nuclear powers - France, China, and Britain - should also make the commitment. He called for a US Soviet summit to discuss the dramatic plans to reduce nuclear arms. "George Bush's proposals continue the drive started in Reykjavik," Gorbachev said, referring to the site of the 1986 US-Soviet summit. "This is my opinion," Gorbachev continued. "I know that [Russian President] Boris Yeltsin and leaders of other republics share this opinion." The eight days it took Gorbachev to respond to Bush's plan reveal just how complicated the defense decision-making process has become here, Soviet analysts say. The approval of the Defense and Foreign Ministries is no longer sufficient. Any military decision, whether they involve nuclear arms control or conventional matters, must have the support of the remaining 12 republics. A top US military official visiting Moscow through the weekend notes that while the Bush plan was warmly received, Soviet counter-proposals were slow to develop. United States Air Force Chief of Staff Merrill McPeak says he found the Soviets "a bit overwhelmed with the pace of change in this country - of all kinds." Soviet observers say the delay was not simply a matter of analysis, but also paralysis. "Now, in this country there's no single command. No one can give a response without consulting many people," says Igor Sedykh, a veteran political analyst for the Russian Information Agency. Though Gorbachev has announced the Soviet proposals for international consideration, he still faces domestic obstacles. Ministries on the union and the republic levels remain at odds over jurisdictional issues, ranging from conventional forces to control over nuclear facilities. Recent Soviet announcements on conventional arms cuts have been confusing and contradictory. For example, Defense Minister Air Marshal Yegeny Shaposhnikov said last Tuesday that troop levels must be reduced from roughly 3.7 million to 3 million. Meanwhile, General Pavel Grachevs, Mr. Shaponshnikov's first deputy, said the same day that forces should be almost halved - from 4 million to about 2 million, by 1994. A defense ministry statement later said the cuts would have to be negotiated with the West. General McPeak says a cloud of confusion remains over these plans. He says he did receive clear messages about Soviet distaste for the old military apparatchiks. m not surprised but amused that the general understanding is that the system of [Communist] Party rule is finished," says McPeak. "Party cadres are unemployed and they've been dismissed. They are the object of rather pointed sarcasm [among present military officers]," he says. The general says the the Soviets are "rethinking the whole ideological basis of their armed forces." The Marxist-Leninist approach mandated that political cadres were stationed at each [military] command level, to insure an ideological purity in the setting they created." PERHAPS the most difficult change for the Defense Ministry will be its planned transformation to civilian leadership, as Shaposhnikov announced. "It's a change, and change is difficult for people," says McPeak. Tough transitions are inescapable in the republics on the Soviet Union's southern rim, where the Communist Party essentially remains. In Azerbaijan, for example, President Ayaz Mutalibov, widely reported to have backed the coup conspirators, shows no sign of easing his iron grip on the republic. The Communist-dominated parliament in Tadzhikistan staged what opponents call a legislative putsch by installing former party boss Rakhmad Nabiyev as president. McPeak says he has the "impression that they [the Soviets] are as concerned about this as we are." The US general says the historic arms initiative from his commander in chief has better positioned the Soviet center in dealing with the nuclear arsenals remaining in the republics. The arms reductions proposals from Washington are "just in time to prevent serious situations from developing involving tactical nuclear weapons," says Blagovolin. "Some republics have nuclear weapons. Our process of political confrontation and reorganization is far from bottoming out, and Bush's proposals will force us to deal with the issue of nuclear weapons."