A new innovative method to measure the cost of war: future with fewer conflicts via harm reduction approaches.

Background: The destruction of World War I (WWI) and World War II (WWII) changed the world forever. In this analysis, the economic costs of WWI and WWII are considered via a harm reduction approach to highlight the cost of war via the mortality of military personnel. The harm reduction philosophy and homeostasis of a biological cell are utilized as a pragmatic approach and analogy to give a greater context to the findings, despite the omission of civilian casualties and military disabilities.

Methods: Tangible (e.g., loss of wages, productivity, and contributions) and intangible (e.g., quality of life) costs are estimated based on the value of each military personnel derived from secondary data and a mathematical model. This is the first study to estimate the cost of war based on soldier's mortality during the first and second World War.

Results: Based on the tangible value, the WWI and WWII cost for the military personnel was US$43.204 billion ($13 billion ≤ α ≤ $97 billion) and US$540.112 billion ($44 billion ≤ α ≤ $1 trillion). When the intangible cost is considered, it is estimated that the WWI cost was beyond US$124 trillion ($43 trillion ≤ β ≤ $160 trillion), and the WWII cost was above US$328 trillion ($115 trillion ≤ β ≤ $424 trillion). The sensitivity analyses conducted for WWI and WWII demonstrate different ranges based on tangible and intangible values.

Conclusions: In the current climate of increasing hostilities, inequalities, global warming, and an ever-changing world, economic prosperities are directly linked to peace, stability, and security. Therefore, any future decisions for military conflicts need to increasingly consider harm reduction approaches by considering the cost of life and potential disabilities for each nations' soldiers, sailors, and pilots.