sentences:  All of these developments were Reagan Doctrine victories, the doctrine's advocates argue, laying the ground for the ultimate dissolution of the Soviet Union.Michael Johns later argued that "the Reagan-led effort to support freedom fighters resisting Soviet oppression led successfully to the first major military defeat of the Soviet Union ... Sending the Red Army packing from Afghanistan proved one of the single most important contributing factors in one of history's most profoundly positive and important developments".Among others, Margaret Thatcher, Prime Minister of the United Kingdom from 1979 to 1990, credited the Reagan Doctrine with aiding the end of the Cold War.