Over the years, the Marine Corps has taken more than a few pages from ancient Greece’s playbook to inculcate a warrior ethos in our ranks. We view ourselves as modern-day Spartans—fast, lethal, and austere. While we’ve proven highly effective fighting in rugged environments for nearly a decade now, our energy consumption is far from Spartan. In fact, the service currently consumes in excess of 200,000 gallons of fuel per day in Afghanistan. Because of that demand, we’re not as light and agile as we once were. This puts both our Marines and our expeditionary capabilities at risk.