War Exhaustion

War exhaustion measures how much a country's society and economy have been worn down by war. It runs from nothing to full exhaustion. In 1946, the countries emerging from the Second World War begin already carrying a share of it, which must be worked off before they can sustain major new campaigns.

What causes it

War exhaustion grows above all with losses. Each month a country gains exhaustion for the soldiers it lost in battle, and for its dead from any nuclear strike, as a share of its population: losing a quarter of one percent of its people brings a country to full exhaustion. A long but limited war with few casualties therefore stays bearable, while a war of heavy losses exhausts a country quickly. For comparison, casualties on the scale of America's in Korea, about a tenth of a percent of the population, come to roughly 40% exhaustion.

Other sources add to it:

• Strategic bombing adds exhaustion to whoever holds the bombed provinces (see Air and Naval Warfare).
• Blockade adds exhaustion every month in proportion to the share of the country's ports under blockade, 1% a month under a complete blockade.
• Mobilization adds a steady monthly drift while wartime laws are in force: 0.5% each for Full Mobilization readiness and Mass Mobilization recruitment, 0.4% for War Production procurement and 0.3% for Universal Service. A country on all three of the heaviest laws reaches full exhaustion in about six years of total war even without losses.

The Monthly War Exhaustion Change modifier raises or lowers the monthly drift, and some armies, such as those fighting a protracted people's war, tire far more slowly than others.

Recovery

At peace, war exhaustion recovers by 1.5% a month, plus more with social spending. The country's military laws then set the pace. Peacetime laws add their own recovery: Demobilized readiness 0.5%, Peacetime Readiness 0.3%, Minimal Procurement 0.4%, Replacement Only 0.2%, a Volunteer Force 1%, and welfare laws up to 1%. The wartime drifts above keep applying after the peace. A country that keeps Full Mobilization, Mass Mobilization and War Production in place after a war recovers only 0.1% a month, while one that demobilizes fully recovers about 3.4%.

Demobilizing quickly after a war is therefore the main lever for recovery, at the cost of an army that needs time to reach fighting trim again.

Effects

The effects scale linearly with the level of exhaustion:

At half exhaustion each effect is half as strong. A war-weary country thus struggles to field fresh brigades, loses revenue just as the war costs it most, and faces growing discontent at home, all while its enemies find it easier to force terms on it.

Exhaustion and peace

War exhaustion is one of the main inputs to leverage in peace negotiations: the more exhausted a country, the more readily it accepts ceasefire and peace terms. AI countries weigh their own exhaustion against breaking a ceasefire, and an exhausted war leader is a prime candidate for a negotiated end. In scripted conflicts such as the First Indochina War, a long war without victory turning opinion against it is what brings a colonial power to the table (see Wars).