Insubordination is the act of willfully disobeying a lawful order of one's superior. It is generally a punishable offense in hierarchical organizations such as the armed forces, which depend on people lower in the chain of command obeying orders.
Sixteen blindfolded partisan youth await execution by German forces in Serbia, August 1941. Allegedly, German soldier Josef Schulz refused to take part in the action and was executed along with the youth.
William Lendrum Mitchell was a United States Army officer who is regarded as the father of the United States Air Force.
Mitchell, c. 1920s
Mitchell as assistant chief of Air Service (in non-regulation uniform)
The French-built SPAD XVI which Mitchell piloted in the war, now exhibited inside the National Air and Space Museum in Washington, D.C. The SPAD XVI, an observation and bomber aircraft, has a Lewis twin machine gun mounted in the rear cockpit.
Mitchell posing with his Vought VE-7 Bluebird aircraft at the Bolling Field Air Tournament in Washington, D.C., held on May 14–16, 1920