Attempts to create an army of fighters who did not feel fear, fatigue, cold and other feelings were conducted back in the middle of the 20th century. So, during the Second World War, American soldiers were given amphetamine pills for this purpose, now officially considered a dangerous drug. It is also known that the military showed great attention to other psychotropic substances, but could not get the desired result - the effect of such drugs was too unpredictable. However, this did not stop the work on creating super fighters, but simply switched the attention of scientists to the internal resources inside each of us, which, with a certain skill, can be mobilized and make any person almost completely insensitive to physical pain and the manifestation of emotions.
Such skills, by the way, were perfectly possessed by the Vikings, who once inspired fear throughout Europe and were considered invincible warriors. Experts who have studied their culture have come to the conclusion that before each battle, they fell into a kind of trance, under the influence of which most emotions were dulled, and rage became dominant. At the same time, all doubts, fears disappear in a person, he becomes as decisive as possible, loses sensitivity to pain, fatigue, etc. Science calls this condition "berserk syndrome" and it is believed that it is caused by the effect of self-hypnosis. That is, a person either inspires himself, or inspires him from the outside, belief in his invincibility and strength, and the body then mobilizes all its hidden energy capabilities.
Naturally, even today all the armies of the world would like to have such fighters, so there is no doubt that the study of the "berserk syndrome" is being conducted in most of them. Of course, the humanity of such a method of improving the combat capability of the army is a big question, but a priori war cannot be humane and, as the saying goes, "all means are good." At least, this is more humane than giving soldiers psychotropic drugs, the use of which is far from the best way to tell on their psyche. However, it should be borne in mind that if any army begins to use the "berserk syndrome" during hostilities, what can prevent the enemy from using this method? As a result, this can only lead to even greater losses on both sides and even more bloody wars in the future.