Theoretically, with enough cheap renewable energy, synthetic hydrocarbons could fuel the war machine. It would need possibly big, vulnerable plants to refine,

Theoretically, with enough cheap renewable energy, synthetic hydrocarbons could fuel the war machine. It would need possibly big, vulnerable plants to refine, but so does jet fuel and diesel now. Adding that much electrical capacity is a civilisational task, but an electrical "JP-8 at home" plant in theory is a good security asset, especially for countries with poor oil supply.