A submachine gun is a firearm that fire pistol ammunition in automatic mode like a machine gun. On the other hand, an assault rifles fires a more powerful round in either semi-automatic or fully-automatic modes. Submachine guns were developed by adding stocks and automatic firing capacity to pistols.
Submachine guns were found to be useful in trench warfare during the First World War. Subsequently, these became famous with both police and criminals alike. The Thompson submachine gun introduced after the First World War is probably one of the most well known submachine guns. However, the first submachine gun was developed by the Italians. This was the Villar Perosa. It was designed to fire 9mm Glisenti rounds and was used mainly as an anti-aircraft weapon. Subsequently, the Beretta 1918 was developed which was also based on the former.
During the years following the First World War, the submachine gun became increasingly popular with gangsters. Due to this, some military planners didn’t like the submachine gun and were against its use by regular personnel. However, the submachine gun was very popular with law enforcement agencies. Gradually, the military adopted it and by the time of the Second World War, submachine guns became standard issue.
By the end of the Second World War, USSR had the largest number of submachine guns in circulation. In some cases, whole battalions were equipped with submachine guns only. Even in the hands of inexperienced soldiers, submachine guns proved to be superior in the field because of their high firing rates. Subsequently, the submachine gun was replaced by the assault rifle as the main weapon of war.
Submachine guns can be used more advantageous by fitting them with suppressors. Modern variants of submachine guns such as the British Sten gun and the MP5 come with an inbuilt suppressor. These weapons are favoured by Special Forces and counter-terrorism units.
Submachine guns are effective in close-quarter combat in urban settings. In addition, they also double up as defence weapons with air force personnel, tank crew and naval units. Many law enforcement agencies also prefer submachine guns. However, the recent years have seen a decline in the use of the submachine gun due to availability of better weapons. In addition, submachine guns are also not so effective against body armour which many criminals use.
Over the decades, the use of submachine guns by the military has also seen a decline. Submachine guns were deployed on a large scale during the Korean War and ever since, their use has seen a decline. In the recent years, the submachine gun is being replaced with the Personal Defence Weapon (PDW). This weapon is almost similar to a submachine gun but fires armour-piercing rounds. However, it may be some years before the submachine gun is completely replaced. As of today, the submachine gun continues to be used by many agencies across the globe.