Mikhail Gorbachev and Zdenek Mlynar were friends for half a century, since they first crossed paths as students in 1950. Although one was a Russian and the other a Czech, they were both ardent supporters of communism and socialism. One took part in laying the groundwork for and carrying out the Prague spring; the other opened a new political era in Soviet world politics. In 1993 they decided that their conversations might be of interest to others...