It's hard for many people to imagine going to war and having to take human lives. It's just as hard for a soldier to imagine, but throughout history, most soldiers have been aided in their duty to kill the enemy by using drugs.
According to VICE, Scandinavian Vikings were able to achieve a trance-like state during battle by eating psychedelic mushrooms. Inca warriors were fueled by cocoa leaves and American soldiers in the Vietnam War often used heroine, with 10-15% ending up addicted to it by the time they returned home.
Polish historian Lukasz Kamienski, author of "Shooting Up: A History of Drugs in Warfare," told VICE, "The anthropological evidence shows us that we are not warlike people. It is very difficult to cross the line where we become able to kill fellow humans."
But that line can be crossed more easily by taking drugs.
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One of the most notable examples of this in history is WWII. Nazi soldiers would often take methamphetamine before going into battle, and most had taken Pervitin, a version of crystal meth, before the invasion of Poland in 1939. Publicly, Hitler and the Nazi regime did not condone the recreational use of drugs, but, in private, many of them would take morphine and cocaine.
Kamienski noted that it wasn't just the Germans using drugs during WWII -- the British, Americans and Japanese were too. "My conclusion would be that the Second World War was fought heavily on speed or meth," he said.
Today, most western armies take a very firm stance against hard drug use. Some soldiers returning from Afghanistan and Iraq have reported things like Adderall and energy drinks being available to them to keep their energy up, but compared to the hard drugs available to the military in the past, those seem fairly tame.
Above Photo: U.S. army troops taking a break while on patrol during the Vietnam War