During a visit four years ago to the disputed area of Nagorno-Karabakh, the Armenian population that dominates the enclave seemed as solid and immovable as the rocky hills that surround the region. “We are our mountains,” proclaimed a massive stone statue on the road to the capital’s airport.

The Armenians made that confident claim before drone warfare arrived in the rugged terrain of Karabakh. Azerbaijan’s use of Turkish- and Israeli-made drones has altered the balance of this conflict, putting the tough, battle-hardened Armenians on the defensive. Nearly 800 Armenians have died since the war began Sept. 27, according to official reports; the Azerbaijani side hasn’t announced casualties, but they’re also believed to be heavy.

The Armenia-Azerbaijan conflict may seem a distant, ancient feud. But because drones have proved so potent there, the war is a visceral demonstration of how modern weapons technology can suddenly unlock what had seemed to be “frozen conflicts” and create tempting, dangerous opportunities to shatter the status quo.

Here’s a simple suggestion for Secretary of State Mike Pompeo, who is scheduled to meet Friday with the foreign ministers of Armenia and Azerbaijan: The path to real negotiations and stability in Karabakh could begin with a no-fly zone over the enclave, enforced by the United States, Russia and France, the three co-chairs of the “Minsk Group” that had been fruitlessly attempting to settle the Karabakh issue since 1992.

Pompeo has a big challenge. Russia and France brokered two cease-fires this month, and both failed. What’s needed is a plan that inserts the three big powers more directly in the Karabakh mess and provides a platform for addressing the underlying issues of sovereignty and refugees. The United States also wants to check Turkey, Azerbaijan’s ally, which Pompeo criticized in an interview this week for “coming in to lend their firepower to what is already a powder keg of a situation.”

Both sides now seem more open to negotiation than before, according to a Politico report. Elin Suleymanov, the Azerbaijani ambassador to Washington, said, “We want a substantive conversation.” His Armenian counterpart, Varuzhan Nersesyan, said, “We see no alternative to the peaceful resolution of this conflict based on mutual compromises.”

Earlier in the war, Azerbaijan might have resisted any truce that removed its best weapon, the drone, from the battlespace, even if temporarily. But momentum seemed to tip slightly Tuesday, when an advancing Azerbaijani force in southwest Karabakh was cut off by Armenian forces, leaving the forward troops surrounded and under heavy attack, according to an Armenian source. That might give Yerevan a little more leverage against Baku.

The Armenians of Karabakh are tenacious fighters. Their superiority in artillery and tank warfare that wrested the enclave from nominal Azerbaijani control in 1994 has continued in the fighting that has recurred intermittently ever since.

Today’s drones have exploded this conventional military paradigm. Using sophisticated Turkish and Israeli unmanned air vehicles, the Azerbaijanis pinpointed Armenian air-defense systems in the early days of the war and followed up by attacking heavy artillery pieces, armored vehicles and troop formations. As the United States discovered in its war against the Islamic State, aggressive use of unmanned aerial vehicle (UAV) weapons can deliver relentless punishment.

Armenia lacked enough modern weapons to combat the Azerbaijani drone fleet or to launch a strong one of its own. Armenia’s defenses against drones might improve if it could acquire enough new systems of its own, said one Armenian source. That might allow Armenia to continue a bloody war of attrition, but it’s a survival strategy at best.

Armenia’s vulnerability in this war vexes a nation still haunted by the Ottoman genocide that killed an estimated 1.5 million Armenians in 1915. To Armenians, this fight against a Turkish-backed adversary feels like an existential struggle, not a regional power play.

Now that the utility of drones has been demonstrated so powerfully, other regional actors might consider reigniting their own frozen conflicts. Serbs and Kosovars still nurse bitter grudges from war in the 1990s. Separatists in eastern Ukraine have been fighting a stalemate with Kyiv since 2014. And what about the Turks? Having seen how effective their drones are in battle, will they now turn them against Syrian Kurds who once fought under a canopy of American drones?

Pick your conflict and you can imagine a deadly application of drone warfare. The big powers need some rules for this new game, and Pompeo should start with a no-fly zone for Karabakh.

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