The Dog That Did Not Bark

So why didn't Russia occupy eastern Ukraine while the Ukrainian military presence was minimal and while the shock of the initial movements into Crimea was still fresh?

Five days before the war began, I speculated about what the Russians would do if they decided to invade Ukraine:

First of all, while I'd like all of Ukraine, it is too big for my army to conquer easily. So I'll settle for much less.

I'd encourage Yanukovich to declare autonomous regions in the east, within Ukraine formally, but defended by local militias quietly supported by Russian advisers and weapons. I'd respond positively to Yanukovich's request for fraternal assistance.

I'd also annex the Crimea, claiming that the transfer to Ukraine in the Soviet period was premised on Ukraine remaining part of Russia and so is not valid. It doesn't matter if that stands up legally as a good argument. That's my story and I'm sticking to it. And with the Crimea being majority ethnic Russian, who will complain? Especially with lots of local militias springing up?

I assumed Russia had 100,000 army troops decent troops that could be in a force pool of an invasion.

I made a WAG (wild-ass guess) that Russia could use half of their decent troops (and there are some good ones in there, I'm not being dismissive) and add the same amount of reasonably good Interior Ministry troops equipped as infantry.

My Crimea portion of that invasion scenario was pretty good on the size of the force needed to take the peninsula. I divided the Russian force pool into two elements:

Fifteen thousand paratroopers would be airlifted to Crimea and ten thousand paramilitary forces would cross the Kerch Strait to reinforce the Russian naval infantry regiment and other troops based in Crimea. [Note: This would be 2,000 naval infantry and 10,000 or so non-combat troops.]

The main effort in eastern Ukraine would be 65,000 strong, on the ground.

Forty thousand paramilitary forces would head into eastern Ukraine, with half committed to cities from Kharkov anchoring the northern flank and points south; and the other half in the southern part, especially around Donetsk. These non-army troops would be the visible face in the cities of the intervention. ...

The 25,000 army troops in three motor rifle or tank divisions (or their brigade equivalents) would be divided into three groups, with one division near Kharkov, one near Donetsk, and one in reserve inside Russia able to move against Ukrainian counter-moves against either major city. This operational reserve force would also include 10,000 paratroopers.

I assumed another force outside of the two invasion forces would be made available:

The Moscow garrison of two divisions would be readied as the strategic reserve.

Obviously, the Russians didn't go into eastern Ukraine.

So how did the invasion of Crimea go? Strategypage describes it and I quote it in this post:

The 11,000 Russian troops normally stationed in Crimea are mostly support personnel for the naval bases of the Black Sea Fleet. The exception was 2,000 marines. These were reinforced by another 7,000 troops, mostly infantry and special operations forces flown in or arrived by ship by early March. These were followed by 15,000 more ferried across the 4.5 kilometer wide Kerch Strait that separates Crimea from southern Russia.

The total included a thousand Spetsnaz.

I thought 25,000 Russian troops would enter Crimea. The Russians actually sent in 22,000.

The main difference is that I thought the Ukrainians would resist and that the raising of local militias would be a supporting force.

Since there was no resistance, the Russians were able to use a Spetsnaz-militia force to pretty much take the key terrain of Crimea.

So why didn't Russia occupy eastern Ukraine, too?

Reports of Russian activity inside eastern Ukraine were out early in the crisis, as if Spetsnaz would repeat the local militia strategy to pose as oppressed ethnic Russians.

And even today, there are reports of 30,000 to 40,000 Russian troops near the border with more deeper in Russia available.

So even the eastern wing of my dual offensive seems in line with my estimate.

But Russia did not invade early. Why?

Did the Spetsnaz effort fail and so deny Putin a needed pretext? If so, why not just assert the pretext and go anyway? The pretext was flimsy for Crimea. What was one more?

Did I grossly over-estimate the Russian troops available? And rather than 100,000 troops and Interior Ministry troops being available, only a quarter of that could be scraped up quickly?

If so, Crimea is the priority.

Now Russia seems to have enough troops to occupy the eastern portion of Ukraine--had the troops been available a month ago. Now, these troops may not be enough to fight for, take, and hold eastern Ukraine in the face of Ukrainian resistance.

Or maybe Russia hasn't made nearly as much progress in restoring their military to fight "the big one," when they earned an ugly victory over a small foe since 2008. Perhaps they're still only capable of fighting "the small one." And Crimea was it.

Or at least Russia's military is not good enough to win a bigger war cleanly and quickly. Such a fight would cripple the Putin narrative that the Russian army is awesome.

UPDATE: Lavrov will chat with Gumby Secretary of State Kerry about ending the threat of invasion:

An unexpected late-night call from Vladimir Putin to Barack Obama has raised hopes for a diplomatic solution to the Ukraine crisis. Do not hold your breath Washington D.C.! Putin’s vague assurances that Russia favors diplomacy over tanks were sufficient to lure John Kerry to redirect his plane to Paris for talks with his counterpart on Monday. But, rest assured, Putin’s diversion from arms to diplomacy is designed to test whether he can get the United States to sell out Ukraine without an invasion that would further isolate Russia and inflict serious damage on its economy.

Putin’s diplomats are already making the case for an agreement that creates an emasculated Ukraine comprised of loosely connected regions, each conducting its own economic and foreign policy (and free to join Russia if they wish), with a powerless figure-head government twiddling its thumbs in Kiev. And Ukraine: Say good by to joining the European Union under such circumstances. You are no longer a country.

Ah, surrendering in Paris in the spring! Life doesn't get much better for our chief "diplomat," does it?

One can either interpret this as form of an ultimatum by Russia that they will invade unless Kerry snatches a partial victory from the jaws of defeat by selling out Ukraine.

Or you can go with the explanation that Russia is not capable of easily defeating Ukraine, and hopes that Lavrov can be Lucy to Kerry's Charlie Brown one more time, and save Russia from their own weakness.

I'm going with the latter.