“Our record of learning from previous experience is poor; one reason is that we apply history simplistically, or ignore it altogether, as a result of wishful thinking that makes the future appear easier and fundamentally different from the past.

The best way to guard against a new version of wishful thinking is to understand three age-old truths about war and how our experiences in Afghanistan and Iraq validated their importance:

• First, war is political.
• Second, war is human. People fight today for the same fundamental reasons the Greek historian Thucydides identified nearly 2,500 years ago: fear, honor and interest.
• Third, war is uncertain, precisely because it is political and human.”

Major General H.R. McMaster (US Army, 20 July 2013)