The European Union has just signed a deal to introduce visa-free travel for Turks. The agreement is a milestone not least because news of it will also travel -- to Kiev.

Turkey and Ukraine are vastly different, of course. But they both present the EU with huge challenges and opportunities. How the EU responds will affect not only the size and scope of the EU, obviously, but also the legitimacy and power of the European ideal.

First things first: The chances that Turkey will join the EU remain slight, and Ukraine has yet to be offered even the possibility. The EU opened membership negotiations with Turkey in 2005 only to freeze the bulk of the talks soon afterward. Ukraine has been offered only a trade and association agreement with the EU. There is hesitation on the other side of both of these relationships, too: Ukrainians are as deeply split as Turks over their proper place in the world.

That said, it’s important to note that despite the EU’s misguided reluctance to admit Turkey, the integration process itself has been central to the improvement of Turkey’s economy and business practices. By now, Turkey has at least as much to offer the EU as the other way around.

The Turkish economy has grown at a faster rate than Europe’s in the last several years, and its prospects remain encouraging. This visa agreement is a big step forward and vitally important to both Turkish businesses and ordinary Turks. Under the agreement, Turkey will take back immigrants caught entering Europe illegally, and its citizens will eventually be allowed visa-free travel throughout Europe.

Turkish Prime Minister Recep Tayyip Erdogan has said the deal may usher in “a new era” in Turkish-EU relations. That would be good news for both sides, and the EU should build on this success by reinvigorating accession talks.

Ukraine is a more difficult case. President Viktor Yanukovych rejected an EU offer for greater integration last month. Instead, Yanukovych is flying to Moscow to secure loans of as much as $15 billion, as well as cheaper natural gas and the removal of punitive sanctions.

The EU’s decision not to get into a bidding war with Russia was defensible. Yanukovych presides over a near-bankrupt kleptocracy that he has refused to reform, and any aid the EU provided would have been used to prop up a corrupt and unreliable regime in Kiev, rather than build a functioning economy along the lines of which the IMF has long demanded.

At the same time, the EU must do more to show it cares about Ukrainians’ political and economic future. It should make it clear that Ukraine will not pay too high a price for rejecting Russia’s overtures. The EU might also acknowledge that, if Ukraine ever were to fulfill all the conditions, membership in the EU would be a possibility.

Hundreds of thousands of ordinary Ukrainians have braved both the cold and the riot police for the last three weeks in Kiev to protest Yanukovych’s rule. That suggests they understand that greater integration with Europe -- regardless of whether it ends with EU membership -- has more to offer them than Russia’s bear hug. A failure to acknowledge that understanding would be disappointing not only for Ukrainians but also for the European Union.

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