Banning War

• Author: Craig Forcese
• Pages: 179-190

179

Chapter 23

Banning War

It was with the Caroline case that self-defence was changed from a

political excuse to a legal dorine.

— roBert y jenninGs (1938)1

A  , the Caroline incident and Webster’s formula

went from an example of self-defence, embedded in a broader,

nineteenth-century concept of self-preservation, to the example

of self-defence in international law, with no broader right of self-

preservation. How this happened requires a tour of state practice in

the early twentieth century.

Self-defence remained a minor sideshow in an era where war

was a legal enterprise — a political excuse for a form of force that,

when scaled up to a full war, was fully legal anyway.2 It could matter

only in a legal system that labelled every exercise of force wrong-

ful, unless pigeonholed into discrete legal categories.3 Put another

way, self-defence as a justif‌ication for force only really became con-

sequential when war itself became wrong, and that process took

shape in the 1920s, with the post–First World War settlement. One

key outcome of the Versailles settlement that ended the First World

War in 1919 was the League of Nations.

The League is only dimly remembered today. In her 2003 his-

tory of the Versailles settlement, Margaret MacMillan reports that

“only a handful of historians still bother to study” it: “Its archives,