It has been a while since I focused on the events in Ukraine, so let’s check in and see where things stand now. The Crimea sham referendum seems to have done the trick—no one is really talking about rolling back Russia’s annexation despite the fact that it challenges international norms (Helsinki Accords, etc.) far more than the support of separatists in Eastern Ukraine. Despite more over-flights over the Baltics and other minor military maneuvers, Russia’s irredentism has remained quite inconsistent—only focused on Crimea and some regions of eastern Ukraine and not aimed beyond.
Still, the good news of the limits of Russia infiltration reminds us that Russia has been quite aggressive. The latest news has Ukraine finally winning some battles against separatist groups, retaking territory and Russia providing far less assistance to the separatists it had inspired, supported, organized, armed and staffed. Indeed, defeated separatists have been denied entry into Russia and have even been shot at. It is almost as if they are being treated like potential immigrants. 
It seems that Russia is as fearful about these separatists entering Russia as the West is when thinking about those who went to Syria to fight and might return. This seems a strange comparison since the Russians fostered the separatists whereas Canada, the United States, France, Britain and the others were none too thrilled to see their citizens of Mideast descent going to the battlefields.
Why has Russia and Putin lost their loving feeling for enclaves of ethnic Russians within Ukrainian territory? It might be that despite complaints about the weak Western response that the costs have begun to accumulate. More likely, the original effort beyond Crimea was meant to prevent or disrupt the Ukrainian election. With the election proceeding and with much support for the government from Eastern Ukraine, the short-term desire to mess with Ukraine has now lapsed. That is, Putin may not be such a sincere nationalist after all. That he is more like Serbia’s Slobodan Milosevic, just with more heft.
This is actually good news—cynical nationalists are easier to deal with than true believers. Cynical nationalists will sell out their cause if the costs get too high or if they find a better way to get what they want—which is to stay in power.
Still, this leaves us with some big questions for the United States, Canada, and NATO. The biggest is how best to deter future Russian aggression and reassure the allies of Eastern Europe. The obvious answer is more permanent basing of NATO troops in the countries closest to the bear—the Baltic Republics and Poland. While some talk about a real capability to respond to Russian aggression, it feels more like Cold War déjà vu as U.S./NATO forces would serve as a tripwire. This would guarantee their involvement in any clash involving Russia with its NATO neighbours. When the military head of NATO, General Phillip Breedlove, was in Ottawa this spring he was asked about this and it was very clear from his comments then and since that he was seriously considering exactly this issue.
The problem is that permanent basing is costly. The costs would be borne mostly by the United States and Germany since the countries in the region want these two countries, more than the other NATO members, to make binding commitments. They want the United States because it is the most powerful and would serve as the greatest deterrent to Russian aggression—that any move that might lead to World War III would be less. These countries also want Germany to deploy troops because Germany has been far less credible as a NATO partner lately—not showing up in Libya, not opposing France selling Mistral ships to Russia, and by not taking a more strident stance against Russia.
Yet neither the United States nor the Germans want to spend any more money on defending Eastern Europe. My guess is that the United States will find some kind of semi-permanent basing strategy acceptable. Pre-deploying equipment and regular exercises is quite familiar, given both past practice in Europe and post-1991 basing in the Middle East. Germany? I would not bet either way on it. The current practice of the Baltic air patrol to signal commitment is clearly not enough to reassure their allies nor present any lasting capability to deal with a Russian move.
The only clear prediction one can make is that the upcoming NATO summit in Wales in September will be far more interesting than the average rubber-stamping of agreed upon documents. Whether anything definitive comes out of the meeting is uncertain because of that old NATO requirement—consensus. It may be very difficult to reach an agreement to change course in Eastern Europe. I do expect that countries, mainly the United States, will develop bilateral deals that have the impact of increasing NATO’s commitment—such as more frequent exercises and the aforementioned pre-deployment of equipment.
There is one other certainty: enlargement of NATO, except for Finland and Sweden if their publics are willing, is off the table. So, Putin may have some success to embrace even though Ukrainian membership was already unlikely. But if taking credit for this keeps Russian troops at home and no more appearances by little green men beyond Russian borders, that would be okay.
 One of the core arguments that Bill Ayres and I made about irredentism is that a successful effort can have the impact of a big wave of immigration, which serves to inhibit irredentism.