One hundred years ago this summer, Europe blundered into a World War through miscalculation and misreading their opponent's intentions.

Can history repeat itself? Might the world blunder into war again?

Most analysts dismiss the possibility. Indeed, it is very unlikely that the west would send any of their young men to die for Ukraine.

But the very unpredictability of the situation makes it impossible to dismiss the idea of a general war completely. Who knows what can happen in Moscow or Washington if the tanks roll across the border and Russia invades?

That uncertainty is hanging in the background as tensions rise in the region - the result of Russia's refusal to implement any part of the agreement reached in Geneva last weekend.

National Journal:

Secretary of State John Kerry is not pleased with what Russia is doing in Ukraine. And in a statement Thursday night, he made his displeasure clear.

Russia, Kerry said, is not keeping its word. "Having failed to halt a legitimate political process," he said, "Russia has instead chosen an illegitimate, coercive armed violence to try to achieve—with the barrel of a gun and the force of the mob—what could not be achieved any other way."

The Geneva agreement reached one week ago between representatives of Russia, the United States, Ukraine, and the European Union had four major points. It said that all sides must refrain from violence; that illegally armed groups in Ukraine have to give up their weapons; that government buildings inside Ukraine's border that had been seized by pro-Russian forces had to be returned to Ukrainian control; and that protesters who comply with these demands would be granted amnesty so long as they did not commit capital crimes.

"The Geneva agreement is not open to interpretation," Kerry said Thursday night. "It is not vague, it is not subjective, it is not optional."

"For seven days," he later said, "Russia has refused to take a single concrete step in the right direction."

"The window to change course is closing," Kerry said. And the United States is "ready to act."

Kerry revealed Thursday that U.S. intelligence has found that Russia's "intelligence services and special operators and military intelligence are playing an active role in destabilizing eastern Ukraine with personnel."

"If Russia continues in this direction, it will not just be a grave mistake," Kerry said. "It will be an expensive mistake." It's not clear right now how the U.S. would go about fulfilling that promise.

Earlier Thursday, President Obama said that new economic sanctions on Russia were "teed up," but that he understands that "additional sanctions may not change Mr. Putin's calculus."

Regardless of the sanctions' possible utility, Ukraine definitely is hoping for another hit from the United States. "We have to do everything possible to stop the aggression," Ukrainian Deputy Foreign Minister Danylo Lubkvisky said Thursday, in a plea to the U.S. and Europe to enact more sanctions.

The situation is getting dicier. The new offensive by Ukraine's military resulted in the deaths of 5 pro-Russian rebels, leading to a warning from Moscow that "consequences" would follow any use of its military against "civilians" by the Ukrainian government. To underscore the threat, new military exercises by the 40,000 Russian soldiers on Ukraine's border got underway yesterday. NATO experts say that Russian troop dispositions suggest an invasion is in the offing.

Ukraine's prime minister said that Putin wants to start World War III. That's hyperbole, to be sure. But what Putin wants, and what might happen are two different things and once unleashed, war creates its own logic with no one knowing the full consequences of that action.