Controlling the Eastern Salient

So if Russia tries to hold the corner of eastern Ukraine defined by the Kharkov region in the north down to Donetsk in the south and Mariupol on the Sea of Azov, how many security forces would Russia need to control the region?

I'll assume that Russia takes all of the Luhansk region plus chunks of the Kharkov and Donetsk regions without trying to hold all of the latter two.

Luhansk Oblast has 2.3 million people.

Kharkov city has about half of that oblast's 2.7 million, and with other populated areas I'll guess Russia will need to control 2 million of this region's people.

Donetsk Oblast has 4.3 million people. The city of Donetsk has a million people and Mariupol has under half a million. With other populated areas, I'll assume 2 million people here, too.

So Russia needs to police 6.3 million people.

Assuming Russia needs 2% of the people in security forces, Russia will need 126,000 security forces to pacify the region.

Obviously, not all the security forces need to be Spetsnaz quality--but some will need to be Spetsnaz. A good number can be locally recruited police and paramilitaries. Others can be Interior Ministry troops from Russia designed for this kind of fight. Some will need to be Russian paratroopers from the higher quality force pool, while others could be second and third line motor infantry units that are not part of the most ready portion of the Russian army.

Yet the lower quality troops will suffer higher casualties and commit atrocities and otherwise abuse the people in ways that will potentially alienate the local population.

We didn't have too much of this problem in Iraq because we sent high quality volunteers with a good amount of training into the fight and not draftees as Russia will have to rely on for the bulk of their army in Ukraine. Russia has only about 100,000 decent quality army troops, and Russia surely doesn't want to tie down too many pacifying one corner of the empire.

If Ukraine continues to resist, much of the Russian conventional units allocated to Ukraine will need to stay concentrated to face Ukraine's military to keep it from counter-attacking into Russian-occupied territory. So Russia will need more troops than just the standard COIN level of troops in the eastern region. Some will need to stay formed maneuver units in order to conduct a conventional defense while others behind this screen break down to small units to conduct COIN missions.

And Russia will need to protect the frontier in sufficient density to prevent Ukraine from slipping special forces, irregulars (some recruited from refugees who flee the conquest), and supplies to bolster local partisans. And those Russian border posts trying to control the frontier will be vulnerable to attacks by Ukraine's conventional military.

Under these circumstances, Russia could very well face the temptation to drive deeper into Ukraine to stop this low-level war of attrition--and put themselves in the position of having to occupy even more territory with even fewer local supporters to count on than they can get in the far east of Ukraine.

This assumes Ukraine is capable of carrying on resistance and that the West provides military and economic aid to allow Ukraine to fight on. That's beyond my ability to guess.

But I can say that pacifying even a corner of eastern Ukraine if they resist and have the means to fight will strain Russia's military manpower until they can put sufficient locals into uniform. But even then Russia will need to keep significant regular and Interior Ministry forces in the area to guard the conquest from both internal resistance and a potential Ukrainian counter-offensive.

And if Ukraine doesn't sue for peace after losing that campaign for physical control of the region (and Ukraine will lose that fight--the only question is the price Ukraine inflicts on Russian forces for that win), the cost to Russia to actively defend the gains will go up dramatically.

Just because I can, I'll assume Russia will need 2 good motor rifle or tank division equivalents--or 20,000 troops--in a conventional defense role to hold off the Ukrainian army from just rolling back into occupied Ukraine.

Assuming Russia needs 126,000 security forces just for pacification and assuming local Ukrainians can eventually supply 2/3 of the security forces, Russia would need 42,000 of their own troops, from Spetsnaz to spearhead the fight to good paratroopers to support them, and mostly decent Interior Ministry infantry for security in higher threat areas and limited offensive missions. Plus helicopter units and artillery. Aircraft could be based within Russia. Let's say 22,000 Spetsnaz and paratroopers plus 20,000 Interior Ministry troops.

Until Russia can organize, train, and equip that local 2/3, Russia's first line units will be stretched and will need second and third tier Russian army units and more Interior Ministry troops to hold their ground.

I don't even mention Crimea. The 2 million people there have a lot of pro-Russian elements to staff local security to have a sufficient security force-to-population ratio. And the narrow isthmus to the mainland means that a relatively small Russian conventional force--from the higher quality force pool--can hold their ground in the face of a Ukrainian offensive long enough to allow Russian reinforcements to fly in to the region to hold Sevastopol and to cross the Kerch Strait to march on the base to break any siege the Ukrainians manage to impose if they break through the neck of the peninsula. But that is still probably 5,000 troops of higher quality committed to Crimea.

So out of Russia's perhaps 100,000 decent quality troop force pool, Russia would need 47,000 of them--about half before you even consider the need for troop rotation. You like to have a 3:1 ratio of forces at home to forces in the field. One third fighting, one third recovering from fighting, and one third preparing to go fight.

So already, Russia is at the worst point of our Iraq and Afghanistan combined campaigns during the Iraq surge when our units were either fighting overseas or preparing to go back, sometimes with less time at home than in the field.

Russia can substitute second and third tier army units to lessen the strain on the first line units, but to repeat, that will increase Russian casualties and guarantee outrages that alienate Ukrainians. Will Russia really go all Chechnya on the Ukrainians when Russia supposedly came in to save fellow Slavs?

Eastern Ukraine would be a tougher nut to pacify than Crimea. Russia can certainly occupy the eastern region's main cities and major roads relatively quickly. I don't know if Ukrainians will resist. But if Ukraine resists, I don't know if Russia could hold it at a price they are willing to pay.

On paper, Ukraine is a lovely asset for Russia. But only if Ukrainians cooperate.