Russia has 150,000 troops near Ukraine. What does that mean?

A military analyst explains Russia’s massive troop buildup near Ukraine’s borders.

President Joe Biden has again said that Russia could invade Ukraine in a matter of days. Secretary of State Antony Blinken appeared before the United Nations Security Council on Thursday, narrating a possible course Russia may take as it launches an invasion.

Skepticism is always warranted. But Russia does have 150,000 troops placed at different points along the Ukrainian border, an undeniable threat that makes war possible. Still, it is hard to fully understand what this massive military buildup actually looks like in real time.

Vox spoke to Scott Boston, a senior defense analyst at the RAND Corporation who specializes in Russian military capabilities. Boston focuses on the military side — so he couldn’t fully weigh in on the diplomatic or political dynamics at play among Russia, Ukraine, the US, and Europe. But what he’s been seeing for weeks has created a sense “that it’s been growing over time to something.”

Historically, at least compared to the Soviet era during the Cold War, Russia’s force is small, Boston said, but it’s “essentially an invasion force.”

The buildup means, for Boston, that troops are prepared to invade, if those orders come. And right now, there is no compelling evidence of deescalation on the ground. “We’re really at the point where the next things that we might see really could be the things that Russia would do to actually start an attack,” Boston said. “They don’t have to do a lot else to prepare militarily.”

Having an invasion force does not mean that Russia will use it, Boston said. But if it does, it may take time for the world to fully understand the devastation, as one tactic Russia might use is to jam up communications. “It might be a while before we start to see the cellphone videos, or people getting text messages or phone calls, out of areas where the Russians have entered,” Boston said. And as Russia’s capabilities far exceed Ukraine’s, depending on how this unfolds, it could be catastrophic: an incalculable and incomprehensible tragedy that may be hard for the world to grasp.

“It’s hard for me to say anything other than a sense of alarm or dismay,” Boston said. “I work on the Russian military and land warfare. The fact that my two main subject areas are suddenly in demand is deeply concerning.”

“I would,” he added, “very much like to go back to obscurity now.”

The conversation, edited and condensed for length and clarity, is below.

Jen Kirby

Russia has built up tens of thousands of troops at the Ukrainian border. A frenzy last week suggested a Russian invasion was imminent. Then Moscow talked about a “partial pullback,” a claim the West was skeptical about, maybe for good reason. Where are we now?

Scott Boston

We’re not at the end of the road, but we’ve reached the point that the US intelligence community and a lot of Russia military watchers — particularly in DC, but also more broadly — we’ve been watching this happen for months. You almost reach this point where you feel there’s this sense of inevitability, that it’s been growing over time to something.

In the beginning of December, declassified information in the Washington Post said Russia was planning to grow to over 100,000 [in] battalions, tactical groups, land forces — and we’re there. The president [Joe Biden] said that there are 150,000 Russian military personnel. The 150,000 number is the newest.

We’re now at the point where — with Russian forces largely deployed, potentially to positions from which they could launch attacks — there is no longer a period where we can count on any deal of warning. There’s no longer a period where we should expect that we would see any further movements of units moving across Russia on trains, for example.

For now, it’s a period of essentially tactical warning. But if Russia does decide to do something, it could be any day now, is how I would say it.

Jen Kirby

When you say tactical warning, what do you mean by that?

Scott Boston

We’re really at the point where the next things that we might see really could be the things that Russia would do to actually start an attack.

They don’t have to do a lot else to prepare militarily. They’re not literally up on the border, but they wouldn’t be. That doesn’t give them as much flexibility in where they cross. It’s in their interest to have some ambiguity about what they’re going to do.

That ambiguity, however, comes from the fact that they have a great many things that they could do. They can threaten Ukraine from Crimea, and on the coastline in their south and especially in the southwest. They border, or are, in some cases, already inside Ukraine in the Donbas, of course, as well as in Crimea. They’re in the north, in Belarus, in multiple locations.

The surprise could be “what happens, where does it come from?” Not “does it happen?”

Christina Animashaun/Vox

Jen Kirby

Essentially, if Russia wanted to start a war, there’s not much more it needs. Both in terms of personnel and equipment — everything is kind of in place right now.

Scott Boston

Very nearly, yes.

Part of that depends on how they want to do it, how they want to sequence it. If they wanted to do something smaller, they could have done it a while ago. If they wanted to start with an air and missile and cyber campaign, for example, to go after Ukrainian leadership targets and high-priority military targets, if they wanted to do that before they launched the land operation, they could have done that.

There is at least one thing — I think this is the big one — that I’ve heard multiple analysts say that’s sticking out in my mind. A lot of people have noticed that this time — and in contrast with, say, 2014 [when Russia annexed Crimea and invaded eastern Ukraine] — we are not hearing the drumbeat to the Russian population of the necessity for war.

Now, what does this imply? Well, it could be that, as the US intelligence community has indicated on more than one occasion, Russia could be seeking to carry out a false flag operation that might galvanize Russian attitudes. They might think they could do that quickly and thus preserve potentially both the element of surprise, but also their flexibility. If they spent the last month building their population up: “Let’s go do this, let’s get this done,” then, there wouldn’t be any surprise. They also wouldn’t really be able to effectively back down if they decided not to do it.

Jen Kirby

That makes sense. What I don’t fully understand is what we’re talking about when we say 150,000 Russian troops are at the border. I have this image of Russian soldiers hanging out in tents, but I assume that’s not quite accurate. Can you paint a picture of what this buildup looks like?

Scott Boston

The way the buildup happened, we saw a number of units from farther away deploy to the area before we saw some of the highest-readiness, locally deployed units move.

Some of those units had also deployed there in April last year as part of the earlier buildup. We saw that they were at the one of the garrisons at Yelnya [a Russian town], a few hundred kilometers from the Ukrainian border, near the Belarusian border. But they were at that garrison. We followed them around a little bit, watching them on commercial satellite imagery. That’s where they ended up until about two weeks ago, when all of a sudden we saw Yelnya emptying. So these different units that had been in this garrison suddenly picked up and relocated to positions near the border. Some of those locations were tent cities. Not necessarily a tactical layout. But it’s a field-expedient one, because it’s closer.

If you’ve flushed forces — so that they are to be ready for an attack — they are going to go to ground, they’re going to disperse, they are going to camouflage, they are going to be more difficult to see.

Almost everyone now has sent most of the forces that we would expect. There’s probably still a few on the way, but the very best Russian units now are starting to be represented, like the airborne troops, elements of First Guards Tank Army — they have great names.

Jen Kirby

First Guards Tank Army, you said?

Scott Boston

They formed that unit after they invaded Ukraine, that came together in 2015-2016.

A colleague of mine recently asked, “How long have the Russians been building up on the border with Ukraine?” And I told him, “about eight years now” — which was half-joking, but also, Russia has been systematically building forces on the border. Two combined-arms armies, three divisions in those two armies; four now. They’ve reinforced Crimea. A sizable chunk of the forces that surround Ukraine are Russian units that are permanently stationed there, and that have been reinforced annually, at least, since the invasion of Crimea and the conflict in eastern Ukraine.

Jen Kirby

I’ve seen this described as something like “the largest troop buildup in Europe since World War II.” What does that mean, exactly?

Scott Boston

What makes this different is that this is a deployed force. In a historical sense, all of the armies in Europe are a shadow of their Cold War selves. The force that the Soviet Union, at the head of the Warsaw Pact, had available for combat operations in the 1980s, was larger than the force that has been deployed around Ukraine.

However, they never mounted up and went into jump-off positions and forward loaded fuel and ammunition, and basically threatened to go. There were some scary moments, like the Able Archer incident in 1983, where mutual misunderstandings could have led to a really, really bad outcome.

This is essentially an invasion force. I’m not saying that’s what they’re going to do for certain. But that’s what they have prepared to do.

Let me also just make that that point really clear. It seems to me that Russia’s armed forces and the government forces that might support them have been told to prepare for a large-scale invasion of Ukraine. Whether they get the order to go, or if they get the order to do a narrower option that is smaller in scale or shorter in duration, while they preserve the ability to threaten to do the larger-scale operation, we don’t know what they’re going to do with it.

Jen Kirby

Can I ask — well, why? My understanding is the Ukrainian army couldn’t really hold off the Russians. Russia seems to have amassed enough capabilities to completely overwhelm Ukraine, though they could potentially do it with a lot less resources or personnel. I’m just trying to understand why they have escalated to this extreme level?

Scott Boston

There’s a few things embedded in that are worth teasing out.

As I mentioned, all of the armies in Europe are smaller than they used to be. Russia’s army is 20 percent of the size of the Soviet Army. That has implications because — although I think there is good reason to believe they have substantial advantages in a high-intensity conventional war against Ukrainian forces — they do not have unlimited soldiers. They have a numerical advantage in a military-to-military sense, but they have a relatively small number of personnel to try to occupy an enormous land area with a population of at least 40 million people.

We are assured that the Ukrainian population will rise up and resist. I do not know how many — hard to tell in advance. Russia has a lot of control over how many people they have to manage, because they can decide how much terrain they want to conquer. What this thing looks like in the long run still could really be challenging. There’s a lot that can go wrong for Russia.

Russia also brought forces from practically as far as the coast of the Pacific Ocean. Thousands of kilometers of movement, mainly on trains. They brought combat aircraft, and we’re now seeing combat attack helicopters. They’re positioning all these forces. A lot of it is very visible. Those of us who follow the Russian military are kind of like, “Why are we seeing all this stuff?”

I think that is part of the message. I think they are doing this from the perspective of “Boy, if they just roll over, and we don’t actually have to kill everyone to go do this, then it will be a lot easier for us.” If they’ve calculated that there’s a chance that could work, Russia may have calculated that it’s a twofer. It could put a lot of pressure on Ukraine, which [Ukrainian President Volodymyr] Zelensky, for whatever reason, has basically ignored. If that doesn’t work, then we can always still attack. Russia has to understand there’s a lot of risks in an operation like this.

Jen Kirby

What do you mean by that?

Scott Boston

It’s one thing for [the US and NATO allies] to be like, “Well, we are going to stay the hell out of this thing in Ukraine.” It’s one thing for everyone to be very, kind of academically, “Oh, clearly Ukraine’s not part of NATO, we’re not going to be involved [in sending troops].” It’s another thing for bombs to fall in a village and kill a bunch of innocent civilians, or refugees to start to reach the Polish border, or large-scale civilian casualties. At a certain point: Are we just going to sit here and watch Ukraine burn and do nothing?

It’s not going to feel very satisfying to impose sanctions. Let’s say we impose damaging sanctions. Russia will certainly be arguing, “Well, we’re doing this for what we think are very good reasons; since we think your sanctions are completely unjustified, we’re going to retaliate against you.”

Here’s one of the most concerning things. Russia’s strategic nuclear forces exercise could potentially take place in the next weeks. This is part of a Russian approach: how do we, as Russia, ensure NATO is deterred from intervening?

One of them is absolutely to remind everyone of the available tools in their nuclear arsenal. I don’t even want to get near that. I don’t even want to think about that — the fact that they’re going to be waving this around.

Jen Kirby

That’s all really terrifying. It sounds like what you’re saying is that once you start a war, the idea that it can be a contained thing is not realistic. But that can be so hard to grasp before it happens.

Scott Boston

There’s multiple levels of things we don’t know. There’s a lot we don’t know simply about what kind of information is going to be getting out of Ukraine. As part of a military campaign, shutting down internal communications in Ukraine is entirely a foreseeable thing Russia might do. It might be a while before we start to see the cellphone videos, or people getting text messages or phone calls, out of areas where the Russians have entered.

Let’s say we’re starting to find out what’s happening. It is not going to be clean war. Russia has, at best, I would say, an early-1990s level of precision guided-strike capability compared to the West. So maybe 10, maybe 20 percent, of the munitions they’re going to be dropping from aircraft are precision. A great deal of their firepower is old-school, unguided artillery. GPS makes that a little more accurate. They’ve got some other tools like UAVs [unarmed aerial vehicles; basically, drones] that should help them be a little faster and more accurate with their legacy rocket and cannon artillery. But they are fundamentally indiscriminate weapons. Fighting happens among people. It happens where people live. It’s scary.

The scale is another thing that we don’t really understand. We haven’t had that kind of high-intensity combat, especially between two sides that have relatively modern weapons, in a very long time — certainly haven’t had it in Europe. We might be about to learn a lot of things, or relearn a lot of things, because I think people think they understand what war looks like — in a lot of cases, that might be affected by conflicts that [the US has] been involved in. This will be different, and we don’t know how it will be different.

I personally find it very difficult to stayed detached from from this, because I just think about what it must be like to be there. I don’t particularly envy the Russian soldiers that have to do this. But at the same time, imagine being a Ukrainian soldier, or civilian, and trying to think about how you’re going to defend your home when you are facing an adversary that potentially has enormous advantages in long-range strike capabilities, enormous advantages in air capability, has cyber capabilities that could take out your ability to communicate. Those are areas where Russia has enormous military advantages.

That will probably get you to lopsided outcomes. It’s not that Russian tank crews are going to be so much better than Ukrainian tank crews. But once you get into the melee, modern warfare is just a blizzard of high-explosive blast and fragmentation. It’s a really hostile place for anyone to be in. Russia is largely going to try to fight this at arm’s length, and I think that they have the tools to allow themselves to do that to a significant extent. It is later on, against armed members of the population, or armed former military continuing to resist, where we could see a lot of the Russian casualties.

Jen Kirby

It is hard to stay detached because it just sounds so horrific.

Scott Boston

The thing that really gets me is that no one, no country, will be better off as a result of this war.

Jen Kirby

Russia has been doing these military exercises — in the Black Sea, and Belarus. Is this just flexing their muscles? Is it a dry run? Maybe they’re in two separate buckets, but broadly, what are they doing these exercises for?

Scott Boston

It is a pretty typical action for them to carry out exercises. Since Sergey Shoygu took over as minister of defense in 2013, Russia has brought back what they call surprise combat readiness inspections. That is; on short notice, go out to the field and go train to do your wartime mission kind of thing. It’s part of their increased focus on readiness.

Well, it turns out, of course, that short-notice readiness exercises are a wonderful excuse to have soldiers out getting ready to do something else, too. In this case, it probably strains credibility a little bit that you would transport units from the eastern military districts to Belarus unannounced in order to have an exercise. They probably could have found a place between, like, Vladivostok and Minsk, to have done it on Russian territory if they really want to exercise those guys.

In the Black Sea, specifically, there’s exercises, which is one of the ways they could potentially menace the coastline east or west of Crimea, but particularly west. You’ve probably noticed they have been moving additional surface combatants at least from other fleets into the Black Sea. We have some amphibious warships from the Baltic Fleet and some from Northern Fleet. So all the way up in, like—

Jen Kirby

Like the Arctic Circle?

Scott Boston

Yes, exactly. They’re probably enjoying the weather on the trip through the [Mediterranean Sea] compared to December north of the Arctic Circle. But they came a long ways to hold exercises. I don’t know how much I could expect that they came there to exercise and then just leave.

Jen Kirby

So my general conclusion from our conversation is that there’s very little evidence that Russia has deescalated, at least based on your analysis.

Scott Boston

Although I would love to be wrong, I can’t really point to anything that I find convincing. I would love for them to deescalate. This is for all the reasons that we talked about.

It’s very difficult to imagine that they would go to all this trouble and accept what they think is essentially nothing in response.

Jen Kirby

Well, I guess my question is: can we be stuck in this awful standoff, where Russia is threatening war, indefinitely?

Scott Boston

I don’t know if this is more pessimistic or more optimistic. Years is definitely out; more than a few months is probably a pretty big lift.

Here’s part of why: At a certain point, there’s just going to be a lot more friction keeping them there. You are transporting food and fuel to them, to maintain them in field conditions. It is a higher burden; it probably costs somewhat more, having them out in the fields like that.

But the cost to them would be over time. There are large portions of Russia that have less military force in them than maybe in decades, maybe longer. A lot of Russia is uncovered because they brought so much to Ukraine. At a certain point, your conscripts only serve for 12 months, so your last group of spring conscripts are getting short. They are not in the combat units, but it is unimaginable to me that there aren’t some conscripts in some of the support or combat support units around Ukraine and Crimea, and in Belarus.

I don’t know what reason they would have to prolong being in the position that they’re in.

If I had to guess what happens next — I probably shouldn’t — but I would guess a false flag operation or some provocation. When it happens, we’ll probably know what it is. But I don’t know what it will be. Some provocation to justify military use. And then the question is: how big do they go? How quickly? Do they try to stage some sort of knockout blow that cows the Ukrainian government into giving up quickly? Or do they go isolate Kyiv and try to directly bring about the end? It is very difficult to imagine any of this stuff.

Jen Kirby

It’s really hard.

Scott Boston

I studied the Russian military for a while. One of the things that was noteworthy in Russia’s past uses of force is that they were not maximalist. They do not sign on for large-scale, long-term occupations. They don’t like to tie their hands like that. They also don’t generally like to show you what they’re doing in advance.

There’s a bunch of things about this that don’t quite work. But taken as a whole, it’s still difficult to escape the view that I think they brought their military there to use it in some way, quite likely in a substantial way.

Jen Kirby

Since I do have you, I have to ask you about the mud.

Scott Boston

It never hurts to have the ground frozen instead of muddy. Rasputitsa [apparently “time without roads”; it happens in the spring, from melting snow, and in the fall, from rains, and makes everything muddy] is totally a thing. Rasputitsa ground the German army to a halt in 1941 in October. It was not equipped for invading a country that had practically no paved roads.

By contrast, the Soviets, and now the Russians, they understand what the road and ground conditions are like. The Russian military, because it operates Soviet-design equipment primarily, is extremely well-equipped in terms of highly mobile vehicles with wide tracks that give them low ground pressure with high power-to-weight ratios. They have an understanding of how to operate in that terrain.

But mud is totally a thing. Getting a vehicle stuck is totally a thing; that’s why we have recovery vehicles. I don’t want to overstate the effect on the campaign. But it absolutely is a problem, has been a problem in this region. Some of the areas that they might be crossing in, from Belarus into Ukraine, are from marshes. They will definitely be a lot more passable if the ground is frozen than if not.

But if Ukraine can’t do anything to stop them without relocating and being struck by aircraft when they move around in the open, then there’s only so much the mud will help.

Jen Kirby

What are you looking for next? We’ve now heard about February 20, because that’s the end of the Olympics and the end of these exercises in Belarus. But, if not necessarily date-wise, what are you looking for in the next few days? Or weeks, if we have them?

Scott Boston

I think we’re at the “any day now.” It’s difficult to predict what will happen next. It’s not clear to me how many of [their next steps] will be visible on social media, or clear according to commercial satellite imagery.

Again, it’s difficult to imagine this thing deescalating peacefully, which is really unfortunate. But Russia is the one that chooses the time and place of military action here.

There’s a lot that they can hide, and they’re actually quite good at it. We may have been lulled into a false sense of security by how we saw all these things happening before. But once they really get into it, there will probably be a lot of things that we don’t see.