Two constitutional-law scholars offer a systematic account of how modern democracies erode and what actually protects them. They distinguish two paths of decline: rapid "authoritarian collapse"—the classic coup—and the slower, far more common "constitutional retrogression," an incremental, legal-seeming decay that plays out over years.
Retrogression, they show, proceeds through recognizable mechanisms: constitutional amendment, the capture of courts and the civil service, the centralization of executive power, and the steady squeezing of the press and civil society. Because it is gradual and lawful in form, it rarely trips the alarms a coup would.
They then test which safeguards actually hold under pressure. Some widely trusted defenses—written constitutions, high courts—prove weaker than assumed; others, like a competitive party system, a professional bureaucracy, and ties to international institutions, turn out to be underrated.
The book is both comparative diagnosis and design manual, weighing which institutional arrangements have helped democracies resist decay and which have left them exposed—including a frank look at specific structural vulnerabilities in the United States.