The disinhibiting and pain-numbing effects of drugs make them perfect for turning people into killing machines. In fact, criminals on PCP have been reported to withstand multiple shocks with Taser guns, pepper spray, and Mace, and even direct gunshot wounds to the chest, without slowing down. It's no wonder that so many generals have relied on drugs to bring out the so-called best in unwitting soldiers.

1. Nazi Shock Troops

During World War II, Nazi Germany definitely led the pack in its use of amphetamines, cocaine, and other "performance-enhancing" drugs. In fact, amphetamine pills were included in every German soldier's first-aid kit, and Nazi researchers developed chewing gum that delivered a dose of cocaine with each piece. But that wasn't all! According to a book by German author and criminologist Wolf Kemper on the subject, Nazis on Speed, one of the substances tested by the Nazis in 1944, D-IX, was actually a cocaine-based compound that included both amphetamine and a morphine-related chemical to dull pain. The experimental drug was tested on prisoners of war, and

Nazi doctors found the test subjects could march 55 miles without a rest

before they collapsed. The Nazis hoped that the drug could put some fighting spirit into their armies, which were by that time being defeated on all fronts, but luckily the war ended before production could begin.

2. Thai and Burmese Bandit Armies

"The Golden Triangle"—an area straddling Thailand, Laos, and Myanmar, where poppy plants grow particularly well—has long been a center of the international drug trade, and for centuries national armies, revolutionaries, and criminal gangs have waged war for control of the income it generates. Recently, however, bandits and rebels from all three countries have begun recruiting children, feeding them opium, hashish, amphetamines, and tranquilizers to give them courage, then sending them out on "human wave" attacks. The disturbing phenomenon leaves a huge proportion of the children dead. One adult soldier from Burma who had to fight these poor child soldiers recalled, "There were a lot of boys rushing into the field, screaming like banshees. It seemed like they were immortal, or impervious, or something, because we shot at them but they just kept coming."

3. U.S. Army "Go Pills"

Though amphetamines are essentially off-limits for the civilian population of the United States, American armed forces have long made use of them to enhance the fighting abilities of pilots, soldiers, and sailors, and to keep them awake for long periods of time. Interest peaked in World War II, when all the major combatants on both sides conducted extensive research and distributed large amounts of stimulants to their soldiers. Surprisingly enough, America's armed forces continue the practice to this very day. The amphetamine most often dispensed to American servicemen and women is Dexedrine, short for dextroamphetamine sulfate, also referred to as "go pills." In one April 2002 incident in Afghanistan, pilots from the Illinois Air National Guard accidentally dropped bombs on a Canadian unit, killing four and wounding eight. In the inquiry that followed, the pilots claimed that they were disoriented because they had been forced to take Dexedrine "go pills" by their superiors and would have been declared unfit for combat if they had not.

4. West African Child Soldiers

In the brutal civil wars that have bedeviled West Africa over the last two decades, much of the fighting is done by children who are teenagers or younger. Armed with automatic weapons, the children are rewarded with sex, candy, tobacco, or alcohol—anything that encourages them to fight. However, sometimes the temptation isn't great enough, so their adult commanders often find it helps to ply them with more powerful drugs that inhibit their judgment. In Sierra Leone, Western observers met children between the ages of 9 and 16 who had been given amphetamines, while children of similar age in the militias of Liberian president Charles Taylor were routinely given cocaine, opium, marijuana, and palm wine to encourage their killer instincts. Often dressed in outlandish costumes out of a belief that strange clothing would protect them in combat—a wedding dress with fright wig was a favorite—these children were described by the journalists who met them as borderline psychotic.

Note: The original name of this post was '5 Armies Hopped Up on Drugs.' We've removed one of the five aforementioned hopped-up Armies for further fact-checking. So if you read the pre-edited version and emailed it to your friend with a subject like 'Check out these five crazy Armies hopped up on drugs!' and received an email questioning your counting skills, we apologize.

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