The Twenty Years’ Crisis, 1919–1939 Summary

E. H. Carr wrote this book to examine the failure of the international system between the First and Second World Wars. He criticizes the belief that peace could be maintained simply through international law, public opinion, moral principles and institutions such as the League of Nations. Carr describes this approach as utopian when it ignores power, conflicting interests and inequality among countries. However, he does not argue that morality should be completely abandoned. Instead, he believes that mature political thought must combine realism with purpose. Realists remind us that power and national interests shape international politics, while idealists remind us that political action requires moral goals and a vision of improvement. The book became a foundational work of classical realism because it exposed the weaknesses of interwar diplomacy and the assumptions behind the unsuccessful post-1919 order.

1. The “twenty years’ crisis” refers broadly to the period between the two world wars.

1. The post-1919 order was based partly upon the League of Nations and the principle of collective security.

1. Carr argues that international institutions cannot operate successfully without support from political and military power.

1. Powerful countries may describe arrangements benefiting them as rules that benefit everyone.

1. The idea of a natural harmony of interests can hide serious conflicts between strong and weak states.

1. Realism studies the world as it exists, particularly the role of power and competing interests.

1. Utopianism studies how the world ought to be but may ignore practical limitations.

1. Carr does not accept a simple choice between morality and power; responsible politics must consider both.

1. The failure to revise an unjust or unstable order peacefully may eventually produce violent attempts to change it.

1. Important quotation: “Mature thought combines purpose with observation and analysis.” It means that wise political thinking needs moral goals but must also examine facts, power and practical circumstances.