To understand just how ominous this is, take a look at this map:

Russia has already seized Crimea and is mobilizing its military in key spots along its border with Ukraine, calling that mobilization “exercises.” On the Ukraine side of that border is a majority ethnic Russian region. Oleg Atbashian reported earlier today that pro-Russians in Donetsk, Ukraine are stirring up violence. Russia already used the threat of violence as its pretext for seizing Crimea. It’s not unreasonable to suspect that Putin is behind the riots that Atbashian reported, to use them as a pretext to move into Ukraine and seize not only its majority Russian regions, but also its valuable energy producing region in the east. Russian forces could move in from Crimea as well as from bases inside Russia.

Now, note the position of Belarus, and then read this translated story, from Interfax:

Moscow. March 14. INTERFAX.RU – tactical exercises with units of Force and Air Defense Forces began Friday in Belarus, part of a military aircraft relocated to the preparatory airfields. “Today started tactical exercises with units of a number of compounds of anti-aircraft missile troops Air Force and Air Defense Forces of Belarus,” – said the agency “Interfax” on Friday, the press service of the Defense Ministry. There have been informed that “on March 14 in accordance with the plan check combat readiness of the Armed Forces of the Republic of Belarus was done of the flight Air Force and Air Defense Forces on prepared airfields.”

Belarus is allied to Moscow. If the plan is to move in from both Russia and Belarus, Ukraine will be blitzed from the east and the north. It barely stands a chance. Russia could be expected to seize Ukraine’s east, while Belarus forces might be tasked with taking Ukraine’s energy producing region to the west. Putin might have already struck a deal with his client state to divide Ukraine between them. Such a deal would be in keeping with Russia’s longstanding strategy of building buffer states between itself and the west — Belarus control of Ukraine’s west effectively sets Belarus as a buffer state between Russia and Poland, Romania and other frontier NATO states.

On Thursday, US Secretary of State John Kerry warned Putin to reverse course in Ukraine by Monday or face US and European sanctions. Monday could be too late. By then, the Crimea referendum on joining Russia will have passed (the ballot doesn’t even provide a “no” option) and Russia and Belarus forces will either be poised to move into Ukraine, or may already have.

Update: Russia is laying out its grounds for invasion. Unsurprisingly, the Donetsk riot plays a central role.