Not only did I go behind the Iron Curtain during this period, I had family who lived there. I have friends who were involved in Solidarnosc. I am acquainted with those who risked a lot to deliver "propaganda" behind Communist lines (i.e. books on liberty, the Constitution, etc.). Ask any of them what caused the system to collapse--the collapse of the USSR was essential to the dominos falling across Eastern Europe. And the Soviet Union did not collapse despite Reagan and his policies; it was in great measure BECAUSE of him. The Pope played a significant role, too--but that is another subject entirely.
This ex post facto revisionism fails to understand the mechanics of why Communism collapsed---because then the author and his friends would have to admit that the system itself is flawed, based upon an economic model doomed to eventual collapse. But all the state-controlled economy lovers out there (yes, that means you Buchananites, too)can't accept that without admitting that their dreams of state utopias will never work, no matter how they're slanted.