[I]f there is a moment when the sub-machine gun achieved something approaching professional reverence, it was during the 1980 Iranian embassy siege in London. When the SAS executed their assault – swift, decisive, and meticulously controlled – they did so armed with the MP5, a weapon that had, by then, refined the sub-machine gun concept to its zenith. What unfolded over those brief, violent minutes was not chaos, but choreography: precise entries, disciplined fire and an almost clinical application of force.
But modern soldiers are no longer facing lightly equipped adversaries. The widespread adoption of advanced body armour, incorporating hardened ballistic plates, has fundamentally altered the dynamics of small-arms engagements. Pistol-calibre rounds, the lifeblood of the SMG, simply lack the velocity and energy required to defeat that protection reliably. In operational terms, that’s critical. A weapon that cannot neutralise a threat when it must is not just limited, it’s potentially dangerous to the man carrying it.
Range, too, has become a defining factor. Contemporary engagements rarely conform to the tight, urban or trench-bound distances of the early 20th century, despite recent reminders from conflicts such as those in Ukraine that close combat has not disappeared. Even there, however, the anticipated resurgence of the sub-machine gun has not materialised in any meaningful way. Soldiers require flexibility, the ability to engage at 50 metres or 300 metres without changing weapon systems. The SMG, by design, cannot offer that.
— Hamish de Bretton-Gordon in The sad death of the sub-machine gun