influential president since Roosevelt, leaving his imprint on American politics, diplomacy, culture, and economics through his effective communication of his conservative agenda and pragmatic compromising. During the initial years of Reagan's post-presidency, historical rankings placed his presidency in the twenties. Throughout the 2000s and 2010s, his presidency often scored in the top ten. Many proponents, including his Cold War contemporaries, believe that his defense policies, economic policies, military policies, and hard-line rhetoric against the Soviet Union and communism, together with his summits with Gorbachev, played a significant part in ending the Cold War. In reverse, professor Jeffrey Knopf argues that being labeled "evil" probably made no difference to the Soviets but gave encouragement to the East-European citizens opposed to communism. President Truman's policy of containment is also regarded as a force behind the fall of the Soviet Union, and the Soviet invasion of Afghanistan undermined the Soviet system itself. Nevertheless, Melvyn P. Leffler called Reagan "Gorbachev's minor, yet indispensable partner, setting the framework for the dramatic changes that neither anticipated happening anytime soon". Reagan was known for storytelling and humor, which involved puns and self-deprecation. He had the ability to offer comfort to Americans during the aftermath of the Space Shuttle Challenger disaster. He also had close friendships with many political leaders across the globe, especially the two strong conservatives Thatcher and Mulroney. Reagan and Thatcher provided mutual support in terms of fighting liberalism, reducing the welfare state, and dealing with the Soviet Union. Reagan's ability to talk about substantive issues with understandable terms and to focus on mainstream American concerns earned him the laudatory moniker the "Great Communicator". He also earned the nickname "Teflon President" in that public perceptions of him were not substantially tarnished by the multitude of controversies that arose during his administration. Political influence Reagan led a new conservative movement, altering the political dynamic of the United States. Conservatism became the dominant ideology for Republicans, displacing the party's faction of liberals and moderates. His presidency resulted in Reagan Democrats. More men voted Republican and Reagan tapped into religious voters. He often emphasized family values, despite being the first president to have been divorced. Reagan was also supported by young voters, an allegiance that shifted many of them to the party. He attempted to appeal to black voters in 1980, but would receive the lowest black vote for a Republican presidential candidate at the time. Throughout Reagan's