A Russian witness concurred that Reagan's height and sartorial elegance doomed Gorbachev to defeat in the negotiations. If this were all that was required to defeat the Soviets, then we made a mistake not electing Wilt Chamberlain president and hiring Ralph Lauren to dress him. Imagine how intimidating President Chamberlain would have appeared greeting Gorbachev. Conservatives can stop worrying about Reagan's reputation. That's the way we do things.
Presidents receive credit for the good things that happen in terms of office and blame for the bad.
Then professional historians devote careers to pointing out that life is not that simple. Reagan deserves the same amount of credit for the ending of the cold war that Herbert Hoover deserves for causing the Great Depression. While that may not be fair, it's the way life is. Biography necessarily concentrates on an individual, but it need not ignore context. Some of us, therefore, will disagree with the conclusion that Gorbachev dissolved the Soviet Union because he was charmed so thoroughly by Reagan, even if we recognize that Reagan could be very charming indeed.