After the communist revolution in Afghanistan in 1978, authoritarian actions forced upon the populace by the Communist regime led to the Afghan civil war, with the mujahideen leading the popular backlash against the regime. The Soviet Union was worried that they were losing their influence in Central Asia, so after a KGB report claimed that Afghanistan could be taken in a matter of weeks, Brezhnev and several top party officials agreed to a full intervention. Contemporary researchers tend to believe that Brezhnev had been misinformed on the situation in Afghanistan. His health had decayed, and proponents of direct military intervention took over the majority group in the Politburo by cheating and using falsified evidence. They advocated a relatively moderate scenario, maintaining a cadre of 1,500 to 2,500-men Soviet military advisers and technicians in the country (which had already been there in large numbers since the 1950s), but they disagreed on sending regular army units in hundreds of thousands of troops. Some believe that Brezhnev's signature on the decree was obtained without telling him the full story, otherwise he would have never approved such a decision. Soviet ambassador to the U.S. Anatoly Dobrynin believed that the real mastermind behind the invasion, who misinformed Brezhnev, was Mikhail Suslov. Brezhnev's personal physician Mikhail Kosarev later recalled that Brezhnev, when he was in his right mind, in fact resisted the full-scale intervention. Deputy Chairman of the State Duma Vladimir Zhirinovsky stated officially that despite the military solution being supported by some, hardline Defense Minister Dmitry Ustinov was the only Politburo member who insisted on sending regular army units. Parts of the Soviet military establishment were opposed to any sort of active Soviet military presence in Afghanistan, believing that the Soviet Union should leave Afghan politics alone.