The Twenty Years' Crisis

The Twenty Years' Crisis: 1919–1939: An Introduction to the Study of International Relations is a book on international relations written by E. H. Carr. The book was written in the 1930s shortly before the outbreak of World War II in Europe and the first edition was published in September 1939, shortly after the war's outbreak;^[1] a second edition was published in 1945. In the revised edition, Carr did not "re-write every passage which had been in someway modified by the subsequent course of events", but rather decided "to modify a few sentences" and undertake other small efforts to improve the clarity of the work.^[2]

In the book, Carr advances a realist theory of international politics, as well as a critique of what refers to as the utopian vision of liberal idealists (which he associates with Woodrow Wilson). Carr's realism has often been characterized as classical realism. Carr argues that international politics is defined by power politics. He describes three types of power: military power, economic power, and power over opinion. He argues that political action is based on a coordination of morality and power.^[3][4][5]