Patrick Joseph Buchanan (; born November 2, 1938) is an American paleoconservative author, political commentator, columnist, politician, and broadcaster. Buchanan was an assistant and special consultant to U.S. Presidents Richard Nixon, Gerald Ford, and Ronald Reagan. He is a major figure in the modern paleoconservative movement in America, and his writings, morals, values, and thinking have continued to influence many paleoconservatives.

In 1992 and 1996, he sought the Republican presidential nomination. In 1992 he ran against incumbent president George H. W. Bush, campaigning against Bush's breaking of his "Read my lips: no new taxes" pledge, as well as his foreign policy and positions on social issues. At the 1992 Republican National Convention, Buchanan delivered his "Culture War" speech in support of the nominated President Bush. In 1996, he ran against eventual Republican nominee Bob Dole, but withdrew after getting only 21 percent of Republican primary votes. In 2000, he was the Reform Party's presidential nominee. His campaign centered on non-interventionism in foreign affairs, opposition to illegal immigration, and opposition to the outsourcing of manufacturing from free trade. He selected educator and conservative activist Ezola Foster as his running-mate.

In 2002, he co-founded The American Conservative magazine and launched a foundation named The American Cause. He has been published in The Occidental Observer, Human Events, National Review, The Nation, and Rolling Stone. The original host on CNN's Crossfire, he was a political commentator on the MSNBC cable network, including the show Morning Joe until February 2012, later appearing on Fox News. Buchanan was also a regular panelist on The McLaughlin Group. His political positions can basically be summed up as paleoconservative, and many of his views, particularly his opposition to American imperialism and the managerial state, echo those of the Old Right Republicans of the first half of the 20th century. Since 2006, Buchanan has been a frequent contributor to VDARE.