Not only did the borders deeper in Europe slam shut, but the continent’s leaders announced Tuesday that everyone who crossed the sea to reach Greece would be sent back to Turkey. The edict applies even to those, like Saraj and his family, who are fleeing war.

“They can’t do that to us,” said Saraj, a slight and habitually smiling 19-year-old Iraqi. “The borders must open soon.”

Yet there is no sign they will, even as the boats carrying asylum seekers to Lesbos continue to roll in as ceaselessly as the aqua-blue tides.

The extraordinary flows of people to Lesbos over the past year made it Europe’s main gateway for refugees, an Ellis Island for the 21st century. But now it is a gateway to nowhere.

The transformation can be seen on the faces of those setting foot on the island for the first time: People once cheered, believing that the worst part of their journeys was behind them and that a new life lay ahead. No one cheers now.

And if Europe’s leaders have their way, the flows will soon be reversed, with once-joyous arrivals replaced by potentially ugly scenes as people are rounded up for return voyages across the Aegean.

The island where hundreds of thousands of people glimpsed Europe for the first time could become, for some, their last fleeting image of a new life that never was.

Many say they will not go quietly.

“If we die here, it’s better than going back,” said Sahir Noh, an 18-year-old Iraqi from the minority Yazidi group who travelled to Greece with 28 family members. Islamic State militants “killed 5,000 people in our community and kidnapped 6,000 more. So how can we live there? All we want is protection. Nothing else.”

Europe insists that people will still be able to apply for protection – in Turkey.

The shifts in the continent’s stance – from open borders last fall to tightening controls in the winter to the shock announcement this week that people would be sent back – reflect a dramatic toughening of attitudes toward refugees.

Much about the new policy has yet to be determined; the deal between European Union and Turkish leaders announced on Tuesday is preliminary, with a summit next week identified as the moment to seal it.

But even before then, EU leaders have declared that the most popular route for migrants into Europe – the one that begins in Lesbos – is closed. To prove the point, border crossings across the Balkans snapped shut this week to anyone without a valid European passport or visa.

Hoping to add an extra edge of deterrence, EU leaders also said that those arriving in Greece by sea will be returned. They have not said when the policy will kick in.

And so far, the threat doesn’t appear to be working.

The pace of boat arrivals on Lesbos actually increased after the announcement – more than 1,400 people came on Wednesday alone, the highest figure in more than a week and roughly half the number who arrived during all of last March. Once they are here, they join the tens of thousands of migrants who are effectively trapped in economically ravaged Greece and barred from continuing toward the more prosperous lands of Western Europe.

Authorities say the island’s capacity – about 6,000 – could be breached at any time as ferry service to the mainland is reduced in order to give Athens and other cities time to cope with a migrant backlog that won’t clear.

Everyone can sense the gathering storm.

“It’s a very tense situation right now,” said Marios Andriotios, an adviser to the island’s mayor. “We’ve made all the preparations that we can. But we expect the number of arrivals will only rise. And we are facing the fact that a lot of the refugees will have to be accommodated on the island for a very long time.”

That’s not what they want. Conditions at the island’s two main camps have improved markedly in recent months, after a concerted effort by aid groups and the local government to improve facilities that fell well short of international standards. In the hillside camps, where redbud trees are coming into vibrant bloom, the toilets are now clean and functional; the meagre canvas tents have been replaced by hard plastic housing.

But no one has any illusion that this is home.

“Greece is a great country. There’s humanity here. But we can’t stay here forever,” said Noh, whose family paid smugglers US$3,500 per person for the weeks-long journey out of the war zone that has consumed their native land.

The family had planned to go to Germany. But with the borders in between now closed, they fear they will be sent back to Turkey instead.

Many who arrive here, following the five-mile journey by sea, have only painful associations with Turkey: corrupt and abusive police, greedy smugglers, no jobs for refugees.

Mohammed Wali, an 18-year-old Kurd from Syria, said police intercepted him and his group as they pushed their boat into the Aegean on Turkey’s shore. “They took our phones. They took everything. And they beat us very badly,” he said.

The group was released and succeeded in the next attempt to cross.

But Wali said he would rather return to Syria than go back to Turkey. “Turkey is not a safe country – especially for Kurdish people,” he said.

Europe has said that for every Syrian who is returned to Turkey from Greece, one Syrian refugee will be resettled in Europe. The deal is intended to reward those who patiently wait their turn, while discouraging people from paying smugglers for a perilous sea journey that has claimed more than 400 lives this year.

“It’s risky to try to manage this at sea,” said Antonios Sofiadelis, a Greek Coast Guard commander whose crews rescue people from boats night and day off the coast of Lesbos. “It’s better to shift the management to land.”

But human rights groups say the EU’s plan is legally and ethically dubious. It has more to do, they say, with continental leaders trying to manage political pressure than it does with genuine concern for those fleeing conflicts on Europe’s doorstep.

“What we’re seeing again and again is that people are not being put at the centre of this debate. Instead, fear has taken over,” said Panos Navrozidis, country director in Greece for the International Rescue Committee. “The core values of the EU are really at stake here.”

If Europe truly wanted to help refugees and control flows, advocates say, it would open up legal pathways for asylum seekers to reach the continent, including visas for education and family reunification. Otherwise, people will continue to take to the sea.

“Even if the door closes, with the level of desperation people are feeling, a window will be found,” said Boris Cheshirkov, the Lesbos-based spokesman for the UN High Commissioner for Refugees, the UN’s refugee agency.

Saraj’s case illustrates why. He and his family lived for nearly two years in a city under the medieval dictates of Islamic State occupation. Friends were kidnapped or killed. Saraj received 17 lashes one day for not being in the mosque at prayer time. Had his family been caught fleeing, he said, they would have been put to death.

Reaching Europe was a chance at rebirth: a return to school, job prospects in his chosen field of electrical engineering and a reunion with his fiancee, who fled last year to Germany.

As he and his family wait in a Lesbos refugee camp for Europe to finalise its plans, they cling to a faint hope: that they will be the last people allowed in, rather than the first to be turned back.

“Maybe they will let us cross, and then no one after,” he said. “I hope.”