Political science is considered a science because it isn't just "let's talk politics" or "debate this thing out" like many people think it is. There's a lot of science behind the strategy and thinking for politicians, and how to lead. It is considered a social science, with the analysis of political activity and systems of government.
The communist regime of USSR led by Gorbachev was no longer willing to intervene in the eastern countries, in a time that the countries were facing increasing pressure for freedom and liberties. The success of some early uprising in countries like Hungary endeared other countries to follow suit.
