The history of pepper ball in the United States can be traced back to the 1980s, when some police departments began to use pepper ball guns to deal with protests and riots. Pepper ball projectiles fired by these pepper ball guns contain powdered tear agent, which can control and disperse troublemakers. This weapon was quickly put into the civilian market and used by some people for defense.However, the use of pepper ball guns has caused some controversy and criticism. Some people think that pepper guns cause excessive stimulation to non-combatants and even cause casualties. Therefore, some local governments began to restrict or prohibit the use of pepper ball guns. At present, some states have passed legislation to prohibit the use of pepper ball guns by police or law enforcement agencies, while others have restricted the use of such weapons.It should be noted that the pepper ball gun is not a perfect weapon, it has certain limitations. For example, it can't cause serious injury, but it can cause some pain and discomfort. In addition, it is necessary to have certain skills and experience when using the pepper ball gun, otherwise it may cause excessive stimulation or unnecessary pain to the target.In a word, the history of pepper gun in the United States can be traced back to the 1980s, and its use has caused some controversy and criticism. At present, some states have banned or restricted the use of pepper ball guns, while others have restricted their use. When using pepper gun, we must abide by the relevant laws and ethics, and take appropriate measures to protect civilians and non-combatants.