Germany's Christmas markets have never been so busy. Well-dressed customers, enjoying the greatest economy the country has enjoyed in 20 years, are using record-high incomes to fork out for sweet Plätzchen pastries and cups of boozy Glühwein.
As lunch nears, most of them head to the Döner kebab joints that line the street; those Turkish sandwiches now rival the Bratwurst as Germany's favourite fast food. But the guys behind the counter are not likely to be German citizens.
The lives of the two million Germans of Turkish origin have become the subject of a furious national debate, in a country that has had no economic crisis so can revel in a full-blown identity crisis.
And what a crisis it's been, especially after central banker Thilo Sarrazin published an inflammatory book, Deutschland schafft sich ab (Germany Does Away with Itself), that argued that Muslim Turks were naturally associated with violence and extremism and thus fundamentally unable to assimilate in German society. This led to a heated public debate about Deutsche Leitkultur (core German culture) and a change in tone by Chancellor Angela Merkel, who condemned Mr. Sarrazin but whose comments about "multiculturalism" seemed to take Mr. Sarrazin's side. (Mr. Sarrazin was forced to resign from the Bundesbank board.)
Given all that, you might be surprised to meet Cem Özdemir, who, by some measures, is the most popular politician in Germany at the moment. The handsome 44-year-old is leader of the German Green Party, which seems poised to become the coalition partner in the next government. That means real power; Mr. Özdemir's predecessor was Germany's foreign minister for seven years.
Born in the deeply conservative southwest to Turkish-migrant parents, Mr. Özdemir's ethnic identity is unavoidable. Germans have given his party a big poll boost, just as they embraced this year's World Cup soccer team, which had more Muslim and Slavic surnames than Teutonic ones. At the same time, Mr. Sarrazin's book sold two million copies. What, I ask, is going on?
"These are people from agricultural societies entering a very complex society having a different language and a different religion," he says. "You cannot expect this to work overnight. This is extremely complicated, and it needs so much effort from everybody. And that sometimes gets lost."
He has two urgent messages. To ethnic Germans, he says: Forget the debate about culture; it's over. Let's talk about how to turn everyone living in Germany into a full citizen. To Turks, he says: Forget about Turkey. You're German now, not part of a long-forgotten homeland's diaspora. Start acting like it, learn the language and become citizens.
"I understood very early that it's not us and them," he says. "I was born in Germany, nobody asked me where I wanted to be born. … It's my country. I spoke the local accent and still speak it. My Turkish has improved and I can now appear on TV there, but I still speak German better because German is my first language. And I don't want a dual passport, I don't want a parallel society - none of us want that. We want constitutional republicanism where we are full citizens, not German ethnic nationalism or Turkish laws."
Turks in other countries become liberal and prosperous. It's German policy (including previous Green policies) that rendered the migrants backward; now they have no stake in the economy. "About half of the babies born in Germany to 'foreign' parents cannot become citizens by birth," Mr. Özdemir says. "So let's decide on the goal first. As I see it, the goal should be: We have to make foreigners into citizens. Because it's easier to discuss things from citizen to citizen than from citizen to foreigner."
Even as some members of Ms. Merkel's party resist this idea, her ministers are telling her another hard truth: Because of its economic miracle, Germany will require about 400,000 annual immigrants throughout the next decade, double the current level.
In its official policies, Ms. Merkel's party has accepted immigration, and her key ministers acknowledge that Islam should be a fully accepted German faith. But elections loom in the conservative south, so this is not being said aloud. Mr. Özdemir, though, feels the immigrants have won.
"What is the alternative, a monocultural society, back to the 1950s? Where, you know, it was unthinkable that a divorced lady who remarried could ever become chancellor?" He adds, "Yes, so Angela Merkel herself is one of the biggest beneficiaries of a multicultural society - she should be thankful we live in such a place."