Van Buren, Buchanan, Lincoln, LBJ: By the mid-19th century, politics had emerged as a vocation, a life's work for a worthy man. Each of these four presidents dedicated his life to cultivating the art of politics, bringing decades of experience in the uses of power. Exemplified by cunning and ambition, they were unmatched in the essential skills of forming coalitions, bargaining with adversaries, resolving conflict, and building consensus.