On the second day of the 2020 Armenia-Azerbaijan war, the Armenian military posted a video of one of its surface-to-air missile systems shooting down a surprising enemy aircraft: an Antonov AN-2 biplane. 

As it turned out, it wasn’t a sign of desperation on Azerbaijan’s part that its military was flying a plane first produced in the Soviet Union in 1947, and today used mostly for crop-dusting. Azerbaijan had converted several AN-2s into unmanned aircraft and used them as so-called bait drones. After the Armenians shot down the planes, revealing the positions of their anti-aircraft systems, their forces came under attack from more modern drones. 

It seems strangely fitting that what was also known as the Second Nagorno-Karabakh War, a conflict that has been called “the first war won primarily with unmanned systems” and even the “first postmodern conflict,” could also end up being the last one in which biplanes played a significant role. The conflict between these two former Soviet republics in the Caucasus, on the border between Europe and Asia, was the culmination of tensions that had been building for more than 25 years and intercommunal dynamics that were far older than that. It was in some sense a throwback to a traditional type of war — two nation-state armies fighting over disputed territory — that was far more prevalent in previous centuries. 

But it was also a hypermodern war where unmanned systems played an unprecedented role on the battlefield, and social media played an unprecedented role off it. Though it got relatively little coverage in the international media at the time — coming as it did at the height of the Covid-19 pandemic, a wave of global protests, and a bitter US presidential election campaign — it was in some ways a preview of the much larger war that would break out in Ukraine just two years later, and may yet be seen as the harbinger of a new and potentially devastating era of international conflict.

The Armenia-Azerbaijan dispute is one of the so-called frozen conflicts left over from the collapse of the Soviet Union. Nagorno-Karabakh, often referred to as Artsakh by Armenians, is an ethnically Armenian region within the borders of neighboring Azerbaijan. Violence in the region erupted in the 1980s when authorities in Nagorno-Karabakh demanded to be transferred to Armenia. (At the time, all were part of the Soviet Union.) 

After the Soviet collapse, when both Armenian and Azerbaijan became independent, full-scale war broke out, resulting in more than 30,000 deaths and the displacement of hundreds of thousands of people, mainly Azeris. The first war ended with a Russian-brokered ceasefire in 1994 that left Nagorno-Karabakh as a semi-independent — but internationally unrecognized — territory surrounded by Azerbaijan, and Armenia retained control of some of the nearby areas. Effectively, it was an Armenian victory. 

In the years that followed, the ceasefire was frequently violated by both sides and the underlying issues never resolved. Then on September 27, 2020, Azerbaijan’s forces launched a rapid dawn offensive, beginning 44 days of war. 

This time, it was a resounding success for Azerbaijan, retaking all of the Armenian-held territory around Nagorno-Karabakh as well as about a third of the territory itself. At least 6,500 people were killed before the two sides agreed to a Russian-monitored ceasefire and only a winding mountain road was left to connect Armenia and Karabakh. (Though Russia, the preeminent military power in the region, is a traditional ally of Armenia, it has been hedging its bets more in recent years, particularly since the 2018 protests that brought a Western-inclined, democratic government to power in Armenia.)

Finally, in 2023 — with Russia distracted and bogged down by its war in Ukraine — Azerbaijan launched a blockade of Nagorno Karabakh, eventually seizing the region and causing the majority of its Armenian population to flee. The Republic of Nagorno-Karabakh was dissolved in 2024.    

What made Azerbaijan’s rapid victory possible? One major factor was Turkey’s strong military support for Azerbaijan, a fellow Muslim, Turkic-speaking nation that Turkey saw as a key ally in extending its influence into the Caucasus. Another related factor was Azerbaijan’s deployment of unmanned drones, particularly the Turkish-made Bayraktar TB-2 attack drone, as well as several models of exploding drones purchased from Israel. These weapons proved stunningly effective at destroying the tanks and air defense systems of the Armenian and Nagorno-Karabakh forces. 

“The Armenians and Nagorno-Karabakh had their forces dug in in advantageous positions, and they might have won if this war had unfolded the way it did in 1994, but it didn’t,” Sam Bendett, a senior fellow at the Center for a New American Security and expert on drone warfare, told Vox. “The Azeris understood that they couldn’t dislodge the Armenians in any other way than to send drones rather than piloted aircraft.”

As much as this war was fought under the global radar, these tactics caused a tectonic shift in the prevailing perception of drones as a weapon. From the beginning of the 20-year-long US war on terrorism, unmanned aircraft played an important role, but they were primarily multimillion-dollar machines like the Predator and Reaper that were employed mostly as weapons for remote targeting of specific targets away from declared battlefields.

The Nagorno-Karabakh war showed how large numbers of simple, replaceable drones could turn the tide on the battlefield in a conventional war. As the military analyst Michael Kofman wrote at the time, “Drones are relatively cheap, and this military technology is diffusing much faster than cost-effective air defense or electronic warfare suitable to countering them.”

Lessons learned in the Nagorno-Karabakh conflict were employed in the Ukraine war, when Ukrainian forces made effective use of cheap drones — including, once again, the Turkish TB-2 — to negate the invading Russians’ advantages in mass and firepower. Over time, the evolving use of masses of cheap drones for strikes and surveillance by both sides in Ukraine have made traditional maneuver warfare vastly more difficult, another dynamic predicted by the conflict in Nagorno-Karabakh. Two years into the war, drones are one major reason why the front line often appears stuck in place.

Another way Nagorno-Karabakh seemed to be a harbinger of conflicts to come was in the role of social media in shaping global perceptions of the war. As the media scholar Katy Pearce wrote in 2020, “Armenians and Azerbaijanis in country and those who have settled elsewhere have long battled on social media, and this escalated during the war … For Armenians and Azerbaijanis, whether still in the region or part of the wider diaspora, social media provided a way to participate, and feel engaged.” 

As with Ukraine two years later, this was a war with an extraordinary amount of battlefield footage that was available to the public, and where that footage was captured by the participants themselves via drone camera or smartphone, rather than conventional (and more impartial) war reporters. This allowed both sides to shape public perceptions of what was happening on the battlefield, a phenomenon we’re seeing again with the Israel-Hamas war and the way social media images have driven coverage of that conflict. Journalists attempting to write objectively about the conflict often came under attack online from partisans who objected to what they saw as biased or unduly negative coverage. 

For Armenia, this may have backfired. When Prime Minister Nikol Pashinyan finally signed the ceasefire deal, he faced mass protests and accusations that he had sold the country, in part because many Armenians hadn’t actually believed they were losing the war — until they lost the war. 

Azerbaijan’s offensive was not a straightforward land grab. Nagorno-Karabakh’s independence was not recognized by any other country on earth — technically, not even Armenia — and as far as international law was concerned, Armenian troops were occupying part of Azerbaijan’s territory. There are many such unresolved border disputes and unrecognized semi-sovereign territories around the world today. 

Still, as Thomas De Waal, a senior fellow at the Carnegie Endowment for International Peace and author of one of the definitive books on the conflict, told Vox, “Azerbaijan’s war of 2020 broke a pattern in European security where the assumption was that all these unresolved conflicts across Europe had to be resolved peacefully. Azerbaijan rewrote the rulebook, used force, and as far as it was concerned, got away with it.” 

De Waal suggests the relatively muted international reaction to the war — the US called for a ceasefire but did not sanction Azerbaijan despite calls from some members of Congress to do so — may have been one of a number of factors that led Russia’s government to believe, two years later, that “there was a more permissive international environment for the use of force and there wasn’t going to be as much pushback [to invading Ukraine] as there might have been a decade before.”

Was this brief conflict in the Caucasus a sign of a larger shift? In recent decades, wars of territorial conquest have been rare, and successful ones even rarer. The best-known examples — North Korea’s attempt to conquer South Korea in 1950, or Saddam Hussein’s invasion of Kuwait in 1990 — have prompted massive international interventions to protect international borders. Wars within states, sometimes drawing in international intervention, have been more common. 

“For a very long time after the Second World War, there was a pretty widespread understanding on how the use of force is not a legitimate means of resolving territorial disputes,” Nareg Seferian, a US-based Armenian political analyst and writer, told Vox. “I don’t think many people realize that until at least the First World War, if not the Second, that was just a really normal thing.” The bloody and ongoing international conflict in Ukraine is in many ways quite rare. If that starts to change, a month-and-a-half-long war in the Caucasus in 2020 could eventually be remembered as a pivotal turning point — not just in how wars are fought, but why.