Exploring the personal experiences of Sara Mardini and Seán Binder, two volunteers who were arrested in February 2018 after helping migrants cross safely into Lesbos, Greece, the journalist Alex W. Palmer outlines the complex situation aid workers in Europe find themselves in: increasingly demonized by local authorities while also facing pressure from different ends of the international political spectrum.

Palmer traces the origins of the problem, explaining how, in the early days of the migrant crisis, the grass-roots response embodied the broadly held values of E.U. citizens: to be a place of refuge and compassion, to create a new future from the ashes of two world wars and to set an example based on morality rather than power.

But, as Palmer discovers, this idea was never unanimous, and it was only a matter of time before this compassion and idealism was eclipsed by anger and resentment. Many rejected the idea of newcomers entirely. Terrorist attacks and acts of criminality committed by asylum seekers further worsened collective sentiments and heightened public unease about the challenges of integration. The topic became a pawn for far-right media outlets and politicians, who helped stoke the growing anti-immigrant temper, portraying Europe as on the brink of being overrun by foreign hordes — and aid workers as part of the problem.

A highly politicized issue, the debate surrounding the migrant crisis continues to rage. As volunteers are targeted, what’s next for migrant aid in Europe?

This story was written by Alex W. Palmer and recorded by Audm. To hear more audio stories from publications like The New York Times, download Audm for iPhone or Android.

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