Challenging liberal constitutionalism
"Carl Schmitt ranks among the most original and controversial political thinkers of the twentieth century. His incisive criticisms of Enlightenment political thought and liberal political practice remain as shocking and significant today as when they first appeared in Weimar Germany. Unavailable in English until now, Legality and Legitimacy was composed in 1932, in the midst of the crisis that would lead to the collapse of the Weimar Republic and only a matter of months before Schmitt’s collaboration with the Nazis. In this important work, Schmitt questions the political viability of liberal constitutionalism, parliamentary government, and the rule of law. Liberal governments, he argues, cannot respond effectively to challenges by radical groups like the Nazis or Communists. Only a presidential regime subject to few, if any, practical limitations can ensure domestic security in a highly pluralistic society."
There's no denying Schmitt's importance or avoiding his influence.
Schmitt is a renowned, though notorious, jurist and political theorist. His other works include The Concept of the Political, Political Theology, Theory of the Partisan, Dictatorship, and Political Theology.
Schmitt influenced thinkers on the left, like Chantal Mouffe, and those somewhat on the right, like Leo Strauss and Alexander Dugin. This book in particular has been mentioned by Curtis Yarvin (aka Moldbug) as an important text on legitimacy.
And get a closer look at the nature and meaning of constitutional crisis.