Physical desensitizing is something that biologists have long been aware of. Basic training in the armed forces tries to desensitize new recruits to pain. We can desensitize ourselves to the summer heat by turning off the air conditioning, or become desensitized to the cold by walking barefoot in the snow. But desensitize is more often used when talking about negative emotions. Parents worry that their children will be desensitized to violence by playing video games. Soldiers may become desensitized to death on the battlefield. Desensitizing may be natural and desirable under some circumstances, but maybe not so good in others.
Many children were desensitized to violence through ceaseless indoctrination, paramilitary training and participation in various other crimes.
—Andrew E. Kramer, New York