The conflict in Ukraine has begun a chain reaction that may well spark a wider conflict, or at least a deeper economic and diplomatic divide between Russia and the West. The NATO summit has focused most of its attention on the cross-border clash around Donetsk and Luhansk, with Russia barely bothering to hide its role in the rebellion in the eastern provinces. NATO nations have begun talking about a tacit alliance with Kyiv, and perhaps even a more formal partnership, upping the ante:

British Prime Minister David Cameron, the summit’s host, said pressure on Moscow would mount if it did not curtail military action in Ukraine which he branded unacceptable.

“What Russia needs to understand is if they continue with this approach in Ukraine, this pressure will be ramped up,” he told BBC television, adding that U.S. and EU sanctions were already having an effect on the Russian economy.

Ukrainian President Petro Poroshenko, whose forces have suffered a string of setbacks at the hands of Russian-backed separatists in the south and east of the country in the last week, was to meet Obama and the leaders of Britain, France, Germany and Italy just before the NATO summit starts.

The Ukrainian leader is looking for arms, training and intelligence support for his armed forces as well as political support against Russian President Vladimir Putin.

France and Germany oppose Ukrainian membership in NATO, but the alliance has serious concerns about blunting Vladimir Putin’s ambitions before they extend to the Baltic states. Even with the resistance from the core European states, Moscow has picked up on the momentum for Ukrainian support and issued a warning to NATO to stay out of the conflict:

The Kremlin on Thursday underscored Russia’s opposition to NATO membership for Ukraine, warning that such a move could derail efforts to end the conflict in eastern Ukraine, as leaders of the alliance gathered for a key summit in Wales.

Russian Foreign Minister Sergei Lavrov also told the United States not to try to impose its own will on Kiev. …

Lavrov said Ukraine’s attempts to abandon its nonaligned status by joining the NATO alliance could “derail all efforts aimed at initiating a dialogue with the aim of ensuring national security,” according to the Russian news agency ITAR-TASS.

Undoubtedly, this is playing with fire, and not just because it would make Russia angry. An alliance with Ukraine at the member level would force NATO nations to respond militarily to defend Ukrainian sovereignty while under attack. Since that attack is already under way, it would amount to a declaration of war against Russia — and everyone knows it. The question on everyone’s mind in Talinn will be whether Europe wants to go to war to protect a country that hasn’t been part of the European sphere of influence for decades, if not centuries. Geographically, Ukraine is in Europe, but politically and culturally it has been under the Russian shadow most of its existence as a region or state.

That would change with the Baltics, but Russia knows that, or should. And in part, that may be what NATO wants to communicate with this saber-rattling over Ukraine — a reminder that NATO is prepared to fight, perhaps even for non-members, but certainly for those already in the alliance. Barack Obama warned Russia that the alliance would protect the Baltic States earlier this week, but given Obama’s credibility these days, NATO may have decided a little amplification was in order.

Bloomberg reports on the NATO summit from the one place they knew to find Barack Obama. No, seriously:

The issue of contributions will likely become acute now that a hot war has broken out in Ukraine. It’s one thing to rattle a saber, but when it’s only a hilt in an empty scabbard, it’s not terribly impressive. The US has tried for years to get European nations to ramp up their defense spending and invest more in their own logistics, but absent an actual threat that pressure didn’t amount to much. With Putin on the prowl in the east, the EU might start taking their responsibilities more seriously.