For over a century, the United States military has been dropping propaganda leaflets in deliberate psychological operations, or psyops, to achieve success in war. But the key question behind the effort remains unanswered: does it even work?
In 1918, the US released more than 3m leaflets behind enemy lines by plane and hydrogen balloon. To their delight, they found the leaflets helped erode morale and unit cohesion among the Germans in the first world war. Or so the story goes.
