People whom Mr. Vance has cited to explain his worldview or detail who helped shape his thinking include Patrick Deneen, a professor of political science at the University of Notre Dame who has suggested that conservatives must harness the power of the state to counter “liberal totalitarianism”; Peter Thiel, the billionaire venture capitalist for whom Mr. Vance worked; and Curtis Yarvin, a prominent voice on the New Right who has argued that American democracy has devolved to the point that the country needs a monarchical leader.