How will wars be fought and won in the age of autonomous machines and artificial intelligence? War is becoming more machine-intensive, data-dependent and fast-moving. Unmanned systems operate in the air, at sea and on land. Software is collapsing the distance between detection and destruction across a battlefield where almost nothing stays hidden.Yet wars are increasingly becoming contests between systems of adaptation and integration. The advantage lies with states like Ukraine that learn, produce and change faster than their adversaries can counter. Ukrainians have adroitly connected soldiers, engineers, factories, intelligence services, private companies, tech founders and political institutions. Although numbers matter, the ability to alter techniques before the enemy can respond matters more. Drawing on dozens of field trips to Ukraine, frontline access and conversations with commanders, soldiers, engineers, politicians and citizens, the authors show why military innovation cannot be separated from politics. Political institutions are military variables, and political agency, people and values remain central to understanding why societies fight and how they endure.Written from the perspectives of a strategist, intelligence officer, entrepreneur and soldier, War of the Machines reveals what is changing in war, what is not and what we can learn from Ukraine about conflict in the age of autonomous machines and artificial intelligence.