Why did submachine guns become less important as standard military weapons after World War II?

After World War II, the submachine gun lost its status as a standard military weapon primarily because it could not bridge the gap between low-power pistol cartridges and full-power rifle cartridges. While submachine guns were effective for close-quarters combat, their limited effective range—typically around 200 yards—made them insufficient for the broader requirements of modern infantry engagements.12

The emergence of the assault rifle provided a superior solution to this tactical problem. By utilizing intermediate-power cartridges, assault rifles offered a combination of portability, high volume of fire, and effective range that far exceeded that of submachine guns. As these weapons became the standard for modern armies, the role of the submachine gun was largely relegated to specialized tasks, such as use by special forces, police units, and counterterrorist operations.31