An awful lot is riding on this moment. The Med is warming at one of the fastest paces in the world (up to 0.12 degrees Celsius, or 0.216 Fahrenheit a year, on the surface), and it is choked with plastic. Though the Mediterranean constitutes less than 1 percent of the world’s oceans, it holds 7 percent of its microplastics. The coastal states continue to sully the sea with tons of everything from shipping oil to untreated sewage, meaning there’s scarcely an untarnished ecosystem left. (It’s a similar story on land: Naval bases sit alongside garbage-strewn beaches and coastal dump sites—relatively high military budgets juxtaposed with penniless environment ministries.) For the millions of people who depend on the Med for employment, and the many millions more who treasure it as a “blue lung” in a region of sometimes suffocating heat and claustrophobic cities, the sea’s struggles threaten to become their own.

But there might be an even more important subtext to the eastern Med’s decline. For millennia, those who lived near it thrived off one another, always trading and frequently cooperating from coast to coast, creating some of the greatest civilizations in world history. Yet that was long ago, and the region’s intellectual slump mirrors its environmental decay. Stifled by unilateralism, greed, and chronic short-termism, antiquity’s greatest sea resembles the contemporary world in miniature—and with this year’s United Nations climate talks having concluded in Madrid with little tangible progress, the lessons the eastern Med offers are not particularly hopeful.

Read: A blueprint for protecting the world’s oceans

“I’ve come back to the Mediterranean after 30 years and I’m heartbroken,” Gaetano Leone, a native Neopolitan who is now head of the UN Environment Program’s Mediterranean Action Plan (UNEP/MAP) Secretariat, told me. “Are we ever going back to the blue Mediterranean with the best fish and the pristine beaches? I don’t know if it will go back to that impeccable romantic image.”

Some of the Med’s troubles are due to its unusual topography. Because it has few external outlets, it takes roughly 100 years for a drop of water to exit the sea, so there’s less dilution of toxins, and because some of the strongest currents flow west to east, the eastern Med bears the brunt of the entire littoral’s poor practices. But that’s only part of the story.

Conflict has scarred it in ways big and small. Most recently, in Syria, underwater pipelines at the Baniyas oil terminal were sabotaged, sending crude gushing out to the surrounding coastline and beyond, while Gaza’s bomb-damaged wastewater facilities continue to leak raw sewage into the shallows. As ever in war, the environment tends to become a distant concern.

Years of economic and political dysfunction have also left a fearsome mark. Mired in varying degrees of financial crisis, parts of North Africa, Southern Europe, and the Levant have made marine protection even less of a priority. Greece is one of a number of countries to have disregarded some environmental best practices in its clamor for investment. “During the years of crisis, we tried to make as much of our coastline as possible,” Dimitris Ibrahim, a marine-program officer at WWF Greece, told me. “This isn’t just in Greece, of course, but the narrative became that environmental protection is a barrier to growth. People might say: ‘I want a healthy ecosystem to pass to the next generation, but I also need to feed my kids.’”