Andrew Sullivan's rundown on what contemporary chatterers thought of Reagan. Here are a couple of the most spectacularly stupid ones:
"A few years from now, I believe, Reaganism will seem a weird and improbable memory, a strange interlude of national hallucination, rather as the McCarthyism of the early 1950s and the youth rebellion of the late 1960s appear to us today." - Arthur "Always Wrong" Schlesinger, Washington Post, May 1, 1988.
"Are we rushing headlong into the next step of those 40 years of progressions by which we do something then they do something, by which we pretend that we're going to build this and it will somehow strengthen our deterrent then they do it, and low and behold, the next thing we know is, the President of the United States is addressing the nation saying, ‘My fellow Americans, I hate to tell you this, but the Soviet Union is deploying more of these, and we have to respond, and I'm asking the Congress for more money in order to respond.’ Star Wars is guaranteed to do that, and it's guaranteed to threaten the heavens -- the one line we haven't yet crossed with weaponry: the heavens." – Senator John Kerry, on SDI, the program that brought the evil empire to its knees, August 5, 1986.
"In his distaste for bilateral efforts to manage the superpower rivalry and his instinctive predilection for unilateral ones, Reagan is counting on American technological and economic predominance to prevail in the end. The most striking, and questionable, theme in his star wars speech was his apparent belief that the U.S. could mobilize its scientific community and its economic resources in quest of an impenetrable antiballistic-missile shield over the entire nation without triggering perilously destabilizing countermeasures, both offensive and defensive, on the part of the U.S.S.R. Reagan's views notwithstanding, there is little reason to hope that the many handicaps of the Soviet economy will be decisively advantageous to the U.S. in the long run, allowing the U.S. to ‘beat’ the U.S.S.R. in an arms race." -- Strobe Talbott, Time, April 18, 1983.
There are a bunch more, each as ludicrous as those above.
In addition, see Max Boot's column regarding contemporary opinion, Reagan and Bush.