The Arab Spring—and the flow of refugees across the Mediterranean it has produced—has Europeans worried. Viewing this anxiety, one must wonder if the widespread and sometimes self-righteous Continental concern about climate change is more about concentrations of foreigners than concentrations of greenhouse gasses.

Turning climate change from a cause into a policy in Europe required support not only from liberals, but also from conservatives. It is clear that top European officials were warning not only about higher temperatures but, as Javier Solana, the EU’s former High Representative for Foreign and Security Policy put it delicately, “substantially increased migratory pressure” due to climate change. In view of Europe’s struggle to integrate new immigrants from North Africa and elsewhere in the Islamic world, this concern puts former British climate advisor Sir David King’s controversial suggestion that climate change is a greater danger than terrorism into a rather different light. And from this perspective, the migration resulting from the Arab Spring foreshadows, albeit very mildly, what some Europeans may fear.

Ongoing upheaval in North Africa in particular has driven refugees to the continent—mostly through Italy—in numbers substantial by some standards but quite limited compared to some climate change impact projections. Some 40,000 refugees have entered Europe, causing controversies both at their entry points and at border crossings. While initially described as “respectful and friendly” by local officials, thousands of Tunisian and Libyan refugees ultimately “trashed” the Italian island community of Lampedusa before receiving temporary Italian visas that allowed them to reach mainland Italy. Their subsequent efforts to enter France—also part of the European Union’s Schengen Area for visa-free travel—have provoked a reexamination and tightening of European immigration policies.

Initially, French authorities sought to prevent refugees from entering the country by suspending train service and detained many who succeeded in reaching French soil for return to Italy. High-level talks between French President Nicolas Sarkozy and Italian Prime Minister Silvio Berlusconi followed, including a joint statement by the two that the situation in North Africa “could swiftly become an out-and-out crisis capable of undermining the trust our fellow citizens place in the free circulation within the Schengen area.” In the most significant long-term move, EU leaders also began to consider changes to the Schengen regime allowing national governments to close down borders in times of crisis.

German leaders were not too pleased about the influx of people and the possibility of political instability either. Joachim Hermann, the conservative Interior Minister in Germany’s southern state of Bavaria, said “we will not accept the Italian government simply declaring the Tunisians as tourists as a way of pushing them into other countries.” German Chancellor Angela Merkel was more circumspect but also quite clear: “not all people in Tunisia who do not want to stay there can come to Europe,” she said.

European anxiety about immigrants—and especially Muslim immigrants—is nothing new. For quite some time, European societies struggled to integrate them. After the end of the Cold War, fear of potentially disruptive mass migration into Europe’s comfortable societies may well be one of the key drivers of European foreign-policy and security decision making, something perhaps not clearly recognized in the United States. Migration was a major factor in Europe’s long and slow path to intervention in the Balkans in the 1990s. It has been a visible source of tension as the EU has expanded, not only in the case of Turkey’s failed attempt at membership, but also in the debates over Poland and other central and southern European nations. And it has likely been a powerful motivator for post-9/11 efforts to engage with Middle East and North African governments to promote economic development and gradual political change.

German Foreign Minister Guido Westerwelle recently said “we want the strong, engaged, courageous women and men who currently want to leave their country to stay in Tunisia and work together there on the successful development of democracy and the country.” His statement may reflect the goals of Europe’s climate policy as well.