Carl Bildt is a former prime minister and foreign minister of Sweden.
The continuing Greek drama may have transfixed Europe and the world, but the great crisis in Europe's east has not gone away. Ukraine remains under partial occupation by Russian-backed separatists, with intermittent fighting still taking place, despite the Minsk II ceasefire agreement.
The on-and-off fighting in Ukraine's Donbas region since the Minsk deal was signed in February has made one thing clear: If Russia is serious about seeking a solution to the conflict, it should be prepared to endorse the deployment of an international peacekeeping mission and force.
Such a mission could begin the process of rehabilitating the region, allow those displaced by the violence to return and facilitate the reintegration of Donbas into Ukraine with appropriate safeguards and devolved powers.
A useful model for this approach is at hand. Two decades ago, the international community was entering the final phase of efforts to secure peace in Bosnia. But there were also lingering conflicts in Croatia, notably in the Eastern Slavonia region, adjacent to Serbia.
Croatian military offensives, first in early May, 1995, and a second in early August, had taken back three of four United Nations-protected sectors from separatist Serb control. But the most important area, Sector East in Eastern Slavonia, remained under firm Serb control. And, much like Russian President Vladimir Putin on the Ukraine issue today, Serbia's then-president, Slobodan Milosevic, insisted that the issue could be resolved only by direct talks between the Serb separatists and the Croatian government in Zagreb.
The reality, of course, was that the Serb separatists were entirely dependent on the political, military and economic support of Mr. Milosevic's Serbia. And, in the end, Mr. Milosevic agreed to the deployment of a UN mission and force, which was given the task of ensuring the region's demilitarization and return to Croatian sovereignty, after implementing the necessary safeguards for the Serbs living there.
Today, the UNTAES (United Nations Transitional Administration for Eastern Slavonia, Baranja and Western Sirmium) mission is virtually forgotten – not because it failed, but because it succeeded.
To be sure, not every issue in Eastern Slavonia was sorted out then or in the years since; but there is no longer a conflict, and Croatia and Serbia now enjoy constructive bilateral relations. This could be a model for the separatist-controlled areas of Donbas if the political will is there to make such an arrangement work.
But is the Kremlin serious about recognizing Ukraine's sovereignty in Donbas and resuming normal relations with the West?
At the moment, I strongly doubt it. It is worth bearing in mind that Russia has driven every step toward escalation in this conflict – including the establishment of the separatist enclaves.
Indeed, the Kremlin appears to be waiting for Ukrainian President Petro Poroshenko's government to fail and the West to split on the issue and stop taking an interest in its resolution. At that point, perhaps, Mr. Putin will be ready to move against Ukraine to secure his own desired long-term outcome.
But if Ukraine's government and the West remain united, the Kremlin might see that its enclaves in Donbas represent a threat mainly to Russia itself. After all, the grim reality is that the separatist enclaves are in economic free fall, with their societies becoming increasingly criminalized. Donbas risks becoming a sticky situation for which no one wants to take responsibility. As this becomes apparent, Russia's leaders could start to envisage a UNTAES-type solution for the region.
Absent any other arrangement, the Kremlin will have to do just that. Former U.S. secretary of state Colin Powell's doctrine – if you break it, you own it – applies to Mr. Putin's intervention in Ukraine as much as to George W. Bush's misadventure in Iraq.
There certainly are very difficult issues that must be sorted out before a peacekeeping mission could go into Donbas, notably the composition and formal mandate of whatever force is deployed. But, again, if the will is there, these questions should not be intractable.
Such a mission could then ensure the real implementation of the political provisions of the Minsk II agreement. Genuinely free and fair local elections, with the participation of all displaced people and refugees, will never be possible without a substantial international presence.
Today, this idea is sure to be dead on arrival. So was UNTAES in the early discussions on Eastern Slavonia. The Milosevic regime then sounded exactly like the Kremlin now. But tomorrow really is another day, and it is certainly not too early to start exploring options that promise not just to manage the conflict, but to resolve it.
Such an intervention might work – but only if and when both sides genuinely want a solution. We are not there yet. But if both Ukraine and the West stand firm and act to block further Russian efforts at destabilization, that day might come. We should be ready.