THIS year we have seen a record number of refugees trying — and too often dying — to get across Europe’s Mediterranean frontier, propelled by brutal wars, the collapse of Libya and other states, environmental disasters and grinding poverty that both cause and feed on this human misery.

The seemingly unending flow of migrants, on top of earlier flows by economic migrants desperately seeking entry to Europe’s common labor market, has thrown the Continent’s politics and policy makers into crisis, placing support systems under strain and fueling a surge in right-wing extremism.

Given Europe’s commitment to a humanitarian policy, the question is not whether to let the genuine refugees in, but where they should go. The European Union is considering a system of quotas that can both distribute the burdens of refugee protection among participating states and create alternatives so that migrants won’t be forced to pay smugglers to cram them into unseaworthy vessels and dump them near shore, or worse.

Negotiating such a system will be very difficult. Countries have an incentive to free-ride on their neighbors’ benevolence. They also know that it gets harder to send refugees back home the longer they remain, so they offer only temporary safe haven, if that. Some states, like Germany and Sweden, did more than their share in past crises and may want their quotas lowered to reflect this.