Update:

The emergency talks over Ukraine between U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov ended not with a bang, but a whimper. 

The only news from the meeting was that both men agreed that a diplomatic solution to the crisis in Ukraine and the issue of Crimea's annexation needed to be reached. This platitude was the exact same conclusion reached during Friday's phone call between Russian President Vladimir Putin and President Obama.

You would think this meeting didn't take place in the context of a 40,000-strong build-up of Russian troops on the Ukrainian border. Kerry addressed this build-up, speaking of it in terms of atmospheric propriety. 

"The question is not one of right or legality. The question is one of strategic appropriateness and whether it's smart at this moment of time to have troops massed on the border."

Russia wants recognition of its annexation of Crimea as well as the chance to determine what kind of government Ukraine and to do the latter without involving Ukraine's interim government in the negotiations. Ultimately, Russia demands that Ukraine become a loose federation of regions rather than a unified state in order to keep ethnic Russians safe Ukraine from becoming too European and pro-Western. (Kerry reiterated that Ukrainians ultimately get to decide what kind of government they want.)

Unless those things happen, it seems highly unlikely that the troops on the border will be heading east anytime soon. 

Original Post:

As Secretary of State John Kerry readies to meet with Russian Foreign Minister Sergei Lavrov in Paris over the crisis in Ukraine, the future of American-Russian relations (along with the fate of Ukraine) hangs in the balance. 

How we got here:

Following the United Nations (non-binding) vote earlier this week to declare Crimea's secession from Ukraine to be invalid and the imposition of sanctions on Russia by the United States, Russian President Vladimir Putin called President Obama on Friday.

Based on the readouts of the call from both the Kremlin and the White House, it sounded like Putin was finally toying with the idea of coming to some kind of resolution on Ukraine, which has ratcheted up tensions between the two countries to its highest point since the Cold War. Either that or Putin was seeking a pretext for further action in Ukraine.

John Kerry was on a plane back to the United States when a meeting with Lavrov was urgently set for Sunday. The plane diverted to Ireland to refuel and left for Paris where the two men will meet.

What's at stake:

A lot. While defusing the crisis is the ultimate goal, this meeting is between two parties that are not willing to concede on the most major issues. Russia wants nothing less than the United States to accept its annexation of Crimea, which the American diplomatic team is loathe to do. When this condition likely goes unmet, expect Russia to budge very little on any of the joint initiatives that Kerry and Lavrov are ostensibly slated to discuss. 

Common ground:

Earlier conversations between Kerry and Lavrov set a framework to help normalize the situation in Ukraine. Here are the parameters:

This included joint initiatives to stabilize Kiev's economy, promote the decentralization of the country's political system and demobilize pro-Russian and pro-Ukrainian paramilitaries that have blossomed across the country in recent months.

Decentralization allays one Russian fear that Ukraine will become a starkly pro-Western stalwart right next door to Russia.

If Russia is really looking for an out in the crisis, an agreement on a number of these particulars would give cover for Russia to pull back on its saber-rattling about the need to defend the allegedly besieged ethnic Russians living in Ukraine. 

What failure looks like:

Should the sides fail to reach a breakthrough and with Putin and Lavrov continuing to peddle the line that ethnic Russians in Ukraine are in danger, it seems highly possible that the tens of thousands of Russian troops amassing on the border with Ukraine will simply invade.

What success looks like:

Good question.