Vietnam could be considered the war on drugs.
If what I've read is correct, US soldiers were given amphetamine pills "like candy".
[1] http://www.npr.org/sections/health-shots/2012/01/02/14443179...
I'm fairly convinced Hitler was on the gear too.
Amphetamines were still used in 60s as enhancers for mountaineering for example. Most of traditional expeditions to 8000m peaks had the top party high on this, somehow balancing the rush and mental strength it presumably gave with existing in total exhaustion for days and pushing further up. One example out of many is Hermann Buhl climbing Nanga Parbat, solo, hallucinating, as a first ever ascent of the killer mountain.
People like Messner refused to use these, championing clean 'alpine' ascents, without support, just men with their skills and mental+physical strength facing mountains.