A soldier idles by a Russian-made T-72 tank. A moment later, a missile fired from a drone slams into the vehicle, exploding in an orange flash, blowing the man off his feet and leaving the tank a smoldering wreck.

The scene is one of dozens of aerial videos that were posted online in Azerbaijan last year showing off a new weapon. Over six weeks, it helped the nation regain territory in the Nagorno-Karabakh region that had been held by Russian-backed Armenian forces for more than two decades. The videos show attacks on tanks, trucks, command posts, mortar positions and radar installations.

Smaller militaries around the world are deploying inexpensive missile-equipped drones against armored enemies, a new battlefield tactic that proved successful last year in regional conflicts, shifting the strategic balance around Turkey and Russia. Drones built in Turkey with affordable digital technology wrecked tanks and other armored vehicles, as well as air-defense systems, of Russian protégés in battles waged in Syria, Libya and Azerbaijan.

These drones point to future warfare being shaped as much by cheap but effective fighting vehicles as expensive ones with the most advanced technology.