https://www.realclearpolitics.com/articles/2019/04/02/trump_and_conservatives_its_complicated_but_its_working_139929.html
Donald Trump is not a conventional conservative. Far from it. He’s a populist of the right. His strong appeal to conservatives lies in his nationalism, tax cuts, deregulation, and appointment of originalist judges.
Unlike Ronald Reagan, who had well-formed political ideas, Trump’s notions about public policy come from gut instincts, reinforced by cheering crowds. Their common thread is “Don’t tread on me.”
Trump’s disdain for tradition is the opposite of orthodox conservativism. It is most visible in the wrecking ball aimed at NATO and other allies. If you are rich enough and want our military protection, he says, then pay up or forget it. Prove you deserve our protection. Show us the money.
Trump’s threat to walk away is more credible than that of previous presidents because he is instinctively closer to Robert Taft’s isolationism than to Arthur Vandenberg’s internationalism. The Taft-Vandenberg debate in the late 1940s settled Republican foreign policy for the next 60 years. Vandenberg, who chaired the Senate Foreign Relations Committee, led bipartisan support for President Harry Truman’s policies, including the Marshall Plan and forming NATO. The party’s stance was sealed in 1952 when Dwight Eisenhower defeated Taft for the presidential nomination.