There are only three ways for energy and trade to flow overland between Asia and Europe: through Iran, through Russia, and through Azerbaijan. With relations between the West, Moscow, and Tehran in tatters, that leaves onlyone viable route for hundreds of billions of dollars’ worth of trade: through the tiny Caspian Sea nation of Azerbaijan.

When you factor in Armenia’s occupation of almost one-fifth of Azerbaijan’s territory, all that is left is a narrow 60-mile-wide chokepoint for trade. We call this trade chokepoint the “Ganja Gap” — named after Azerbaijan’s second largest city, Ganja, which sits in the middle of this narrow passage. And right now, the Russians hold enough influence over Azerbaijan’s rival neighbor Armenia to potentially reignite the bloody Nagorno-Karabakh conflict of the late 1980s and early 1990s — giving them a dangerous opportunity to threaten the “Gap” itself.

Washington benefits whenever Europe reduces its dependence on Russia oil and gas. This is particularly important at a time when Nord Stream 2, a proposed Russian gas pipeline to Germany that will increase Europe’s dependency on Moscow for energy, seems to be an ever-closer reality. Europe depends on Russian natural gas for 40 percent of its needs. In total, almost 200 billion cubic meters of natural gas is now imported from Russia annually due to declining European production and rising demand.

Russia has a track record of using energy as a tool of aggression, and each barrel of oil and cubic meter of gas that Europe can buy from Azerbaijan, Kazakhstan, or Turkmenistan is one less that it must depend on from Russia. Currently, there are three major oil and gas pipelines in the region, which bypass Russia and Iran and run through the 60-mile-wide Ganja Gap: the Baku-Tbilisi-Ceyhan pipeline, which runs from Azerbaijan through Georgia and Turkey and then to the outside world through the Mediterranean; the Baku-Supsa pipeline, which carries oil from the Caspian Sea to the Black Sea and then to the outside world; and the South Caucasus pipeline, which runs from Azerbaijan to Turkey, and which will soon link up with the proposed Southern Gas Corridor to deliver gas to Italy and then to the rest of Europe.

The Southern Gas Corridor is set to bring vital energy resources from the Caspian region through the Ganja Gap. These supplies will be a boon to southeastern Europe, which is currently almost 100 percent dependent on the Russian pipelines.

It is not just oil and gas pipelines that connect Europe with the heart of Asia. Fiber-optic cables linking Western Europe with the Caspian region also pass through the Ganja Gap. The second-longest European motorway, the E60, which connects Brest, France, on the Atlantic coast with Irkeshtam, Kyrgyzstan, on the Chinese border, passes through the city of Ganja, as does the east-west rail link in the South Caucasus, the Baku-Tbilisi-Kars railway. These are set to become potentially vital connections.

The ongoing campaign in Afghanistan has also proven how important the Ganja Gap is for resupplying U.S. and NATO troops. At the peak of the war, more than one-third of U.S. nonlethal military supplies such as fuel, food, and clothing passed through the Ganja Gap either overland or in the air.

A key plank of the Trump administration’s Afghan strategy is pressuring Pakistan to end its support for the Taliban and associated groups. A consequence of this approach toward Islamabad might be that the existing ground and air routes through Pakistani territory, on which a majority of U.S. supplies in Afghanistan depend, could be cut or stopped altogether. Islamabad has blocked supplies once before: for eight months in 2011, after U.S. forces mistakenly killed 28 Pakistani soldiers along the border with Afghanistan during a firefight with the Taliban. Expanding the route transiting Georgia and Azerbaijan through the Ganja Gap would reduce Washington’s dependence on Moscow and Islamabad for moving military resources in and out of Afghanistan.

All this means that Russia will do anything it can to make it difficult for the West to use the Ganja Gap. One of the ways Russia exerts influence in the South Caucasus in through the various so-called frozen conflicts — especially in the Nagorno-Karabakh region. The conflict between Armenia and Azerbaijan over Nagorno-Karabakh started in 1988, when Armenia made territorial claims on the region, which sits within Azerbaijan but is populated mostly by ethnic Armenians. The dispute soon resulted in a bloody war that left about 30,000 people dead and hundreds of thousands more internally displaced. Since 1992, Armenian forces and Armenian-backed militias have occupied almost 20 percent of territory that the international community recognizes as part of Azerbaijan, including Nagorno-Karabakh and all or part of seven other provinces.

Most of the main oil and gas pipelines passing through the Ganja Gap and carrying Caspian energy to Europe are located near the frontlines of the Nagorno-Karabakh conflict, where troops for the two sides still face off. Moscow knows that any major outbreak in violence would threaten the viability of these pipelines. Given Russia’s influence over Armenia, it would not take much to provoke new fighting.

The West’s leverage in Armenia is relatively limited. Last month, former President Serzh Sargsyan’s controversial attempt to hold on to power after his second term as prime minister expired sparked mass protests, which resulted in Nikol Pashinyan, an opposition leader, coming to power. Despite the changeover, however, Armenia’s economy and security apparatus remain under Russia’s sway. Notwithstanding all his populist rhetoric, Pashinyan has reaffirmed Yerevan’s commitment to a strong alliance with Moscow.

The recent events in Armenia were not a color revolution like in Georgia in 2003 or a Maidan-like moment like Ukraine experienced in 2014. It’s no coincidence that Russian President Vladimir Putin was among the first world leaders to congratulate Pashinyan on his ascension. Although Russia sells weapons to both sides in the Nagorno-Karabakh conflict, it is clear that Moscow’s sympathies lie with Armenia. So no one should expect Armenia to make a fundamental shift toward the West.

Indeed, given the strength of Moscow’s ties to Yerevan, the United States and Europe should prioritize relations with Baku as the critical trade, energy, and economic link between the east and west of the Eurasian landmass. The West should strive for cordial relations with Armenia, but the United States needs to be mindful and realistic when setting its strategic priorities in the region. Armenia is largely a lost cause; Azerbaijan, even with all its flaws, is a better bet.

Keeping access to the Ganja Gap is the essence of “principled realism” as outlined on the first page of the 2017 U.S. National Security Strategy. Azerbaijan is the only country in the world that borders both Russia and Iran. Keeping a balance between Tehran, Moscow, and Washington while striving to preserve the country’s autonomy has often been a difficult task for Azerbaijan’s leaders. But unlike U.S.-Armenian relations, since the early 1990s, the U.S.-Azerbaijani relationship has thrived in a number of areas, most notably energy cooperation and — since Sept. 11, 2001 — counterterrorism. Azerbaijan even recently increased its contribution in manpower to Afghanistan. Azerbaijan’s 120 troops in Afghanistan give it a larger troop presence than some NATO members, including Spain (eight), the Netherlands (100), and Norway (54).

There are still sticking points in the U.S.-Azerbaijani relationship. Human rightsissues have been a persistent problem, and in recent years, concerns about press freedom have risen due to a number of high-profile arrests of prominent journalists. While Washington should continue to press for improvements on human rights, U.S. policymakers cannot allow that one issue to create a lopsided foreign policy that undercuts the United States’ broader interests in the region.

The United States is the most important global power ensuring uninterrupted and secure flow of international trade through chokepoints around the world. The free flow of global trade, including U.S. exports, brings huge benefits not only to the global economy, but ultimately to the economy of the United States, too. In terms of U.S. geostrategic priorities, the Ganja Gap should rank close to the top.

The Trump administration’s National Security Strategy emphasizes the need to develop good relations with stable allies. This is particularly necessary in the South Caucasus. Decreasing tensions in the region would help secure vital energy, communications, and trade corridors.

Ganja’s history as a source of trade and commerce dates back to the Silk Road that once crossed Eurasia. Even today, any grand strategy that takes into account a resurgent Russia, an emboldened Iran, and an economically expanding China has to reckon with this tiny 60-mile gap.