If the United States and Europe were thinking rationally, the NATO summit in Wales last week would have been an opportunity to discuss a lasting resolution to the violent crisis in Ukraine, which has claimed thousands of lives and crippled the country’s economy. Instead, amid a fragile cease-fire agreement between Kiev and pro-Russian rebels in the east, the assembled world leaders used the summit for more belligerent talk and reckless saber-rattling, with their ultimate goal increasingly unclear. The goal seemed more preparing the NATO alliance for a new Cold War with Russia than exploring how to make peace, even as Moscow was helping to bring about the cease-fire agreement.

The meeting was just the most recent disturbing example of how cavalierly and cynically the NATO leaders — including President Obama — have escalated tensions, while dismissing opportunities to bring the conflict to a reasonable conclusion quickly. Absent from the discussion in Wales, among other things, was any recognition of NATO members’ own roles in triggering the crisis. Despite the dominant narrative that Russia is to blame for Ukraine’s uncertain future, history tells a different story — one in which the West’s provocative behavior has had predictable repercussions.

There would have been no civil war if the European Union’s leadership had not insisted on an exclusive association agreement that prejudiced Ukrainian industry in the east and trade with Russia, or if the United States and European nations had used their influence with the demonstrators to abide by the Feb. 21 agreement then-President Viktor Yanukovych signed, which would have handed more power to parliament and called for elections in December, or if the United States and Europe had been willing to work with Russia to restore the Feb. 21 agreement and calm worries in Crimea and the east about the rights of Russian-speaking Ukrainians.

Instead the U.S. and E.U. have encouraged the most radical elements in the Kiev government in their campaign to subjugate the east with military force — to seek a military solution to what is essentially a political problem in a deeply divided and economically fragile Ukraine.

Our responsibility goes beyond the immediate crisis, too. There would not have been such a concerted Russian nationalist response to the crisis had the West not sowed the seeds of suspicion and mistrust over the past 18 years by growing NATO’s presence in Eastern Europe, in spite of the assurances that Russia ostensibly received from the George H.W. Bush administration that “NATO will not expand one inch to the east.” Russia clearly views NATO expansion not only as provocative but also as a betrayal of an agreement, and it perceives NATO’s push toward its borders as an act of aggression — and Western leaders know it.

In this sense, NATO expansion is not a consequence of tension with Russia; it is the cause. As George Kennan, known as the “father of containment,” warned some 16 years ago, NATO’s willful expansion would create lasting tension. “I think it is the beginning of a new cold war,” Kennan said in a 1998 interview with Thomas Friedman, reacting to the alliance’s pending additions of Poland, Hungary, and the Czech Republic. “I think the Russians will gradually react quite adversely and it will affect their policies. I think it is a tragic mistake.”

In 2004, NATO admitted seven new members, including the Baltic States along the Russian border. Four years later, the George W. Bush administration failed to win acceptance for Georgia and Ukraine — a bid that faced significant opposition from Germany and France — but the alliance symbolically declared that the countries “will become members of NATO.” Those actions have inevitably colored any developments.

While there is no question that Russia at times has contributed to tensions in the region, what has unfolded was predictable and preventable. The West should have understood that an attempt to bring Ukraine into an exclusive arrangement with the European Union would spark deep, historical divisions within the country and itself, and raise Russian concerns. After all, we have seen this before. “Logic aside,” writes John Mearsheimer in Foreign Affairs, “Russian leaders have told their Western counterparts on many occasions that they consider NATO expansion into Georgia and Ukraine unacceptable, along with any effort to turn those countries against Russia — a message that the 2008 Russian-Georgian war also made crystal clear.”

Yet the hawkish outcry for a more confrontational stance toward Putin has yet to give way to common sense. Across the political spectrum, prominent figures are demanding harsher sanctions targeting Russia, as well as military assistance and NATO membership for Ukraine. These demands seem to increase regardless of what Moscow does and regardless of the fact that Russian cooperation is essential for the stabilization and rebuilding of the shattered Ukrainian economy. Never mind that Putin has just helped broker a long-sought cease-fire; sanctions, we are told, must be broadened and deepened. Punishing Russia is far more important than a political settlement in Ukraine.

It is long past time for sober reasoning and comprehensive negotiations to end the bloody conflict. Fortunately, the parameters of a peaceful resolution are well established, and we have the cease-fire to build on.

First and foremost, any possible membership of Ukraine in NATO or the stationing of NATO forces on Ukrainian territory must be firmly excluded. As I have written before, Ukraine’s chances for recovery depend on positive relationships with both Europe and Russia. There is only one way for Ukraine to stabilize, and that is as a bridge between Russia and the West, not a champion of either.

Second, Ukraine should adopt a federal system that provides more autonomy for the eastern region and protects the rights of its Russian-speaking population. The E.U., Russia, and the United States should devise a joint plan to rescue the rapidly shrinking Ukrainian economy. Finally, the Organization for Security and Co-operation in Europe should place observers and peacekeepers to monitor progress in the war-ravaged east.

This is a fateful moment. The cease-fire is a positive step, but it may well be short-lived. For now, with NATO and Russia both preparing for the worst-case scenario, it is more important than ever to stop the triumphalist rhetoric and refocus our efforts on ending the conflict, not escalating. Make no mistake: there is no military solution to this challenge. Only a reasoned dialogue and political settlement can put Ukraine on the path to long-term stability and peace.

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