One of the most fascinating theories that I've read on this is that this was the result of a secret alliance between Reagan's CIA and the Catholic Church. The basic outlines of the alliance was that the CIA supplied money and material on non-violent resistance (through deniable channels), the Catholic Church supplied the network and connections that could distribute them. Also the two aligned on other things, such as tying US foreign aid to abortion policies that the Catholic Church liked.

What does Poland have to do with all of this? Pope John Paul II was Polish, and so their test became the Solidarity movement in Poland. After that proved a success, they replicated it throughout the Eastern Block.

I first read this theory in a Mother Jones article back in the 1980s. And every so often I wish I could find it to read it again.