Abstract There have been many accounts of Donald Trump's assault on America's constitutional norms and institutions. Journalists have detailed how a real estate mogul and reality television star with no experience in public office captured the Republican Party and disrupted the regular protocols of the executive branch. Legal scholars have lamented Trump's politicization of the Justice Department breaking through the fragile guard rails put in place in the wake of the Watergate scandal. Psychiatrists have sought to diagnose Trump's politics of resentment, which they attribute to the rage and narcissism of a sociopath. Amid this frenzy John Campbell's Institutions Under Siege: Donald Trump's Attack on the Deep State provides a comprehensive study on Trump's assault on American political and government institutions. He shows persuasively that Trump's presidency had a deep and dangerous imprint on elections, the Republican Party, the bureaucracy, and fiscal policy. Critically examining Campbell’s theory and evidence, this essay considers where Trump stands in the long train of democratic crises that have occurred throughout American history, how his presidency and its provocative aftermath were a symptom of long-standing changes in the relationship between the presidency and the party system, and why the presidency itself might be a polarizing institution.