If Russia invades Ukraine this will be very bad for Ukraine. This has led many commentators to assume that invading Ukraine would be a great victory for Russia and a great defeat for the US and its allies. Actually the opposite is true. Ukraine doesn't matter geopolitically, and therefore the suffering of Ukraine also doesn't matter. What Ukraine does represent is a huge military distraction for Russia (as Iraq and Afghanistan were for the US) and a huge advertisement for NATO membership.
1. Ukraine's suffering doesn't matter
I am not saying that it is not very sad to think about a country being invaded and its people (at least partially) occupied and subjugated by its neighbour. I would certainly feel very sorry for the poor Ukrainians who have to suffer this. However, their suffering doesn't matter in itself. Geopolitics is not a game of good vs evil where 'bad guys' get points for advancing the cause of evil and 'good guys' lose points for failing to stop them. The state of Ukraine has been pretty bad for most of the last 30 years (just like its other neighbour, Belarus). It didn't matter then and it won't start mattering now just because Russia makes itself the cause of Ukraine's suffering.
2. Bad for Russia
Russia has rebuilt a powerful military. Invading Ukraine would be difficult but certainly quite achievable. Does this mean invading Ukraine would be a great victory? No, because invading Ukraine has costs but no real benefits - because Ukraine doesn't matter.
The exact costs of invasion remain unclear. Some Russian soldiers will die and some expensive equipment used up or destroyed - how much depends on the performance of Ukraine's military. But then there is also the cost of occupation, tens of thousands of soldiers indefinitely unavailable for anything else you might want to do or threaten to do. As the US found when it 'triumphed' in Afghanistan and Iraq, occupying other countries is massively expensive and distracting, even for a superpower that spends more on its military than the rest of the world put together. Russia is not a superpower, and its economy is smaller than Italy's.
3. Good for NATO
NATO was invented to deter the Soviet Union from attacking Western Europe. The death of the Soviet Union rendered its mission unnecessary. Since then it has scrabbled about for reasons to continue to exist. No one has been very convinced and its members' commitment and interest fell away. (Military spending and readiness has declined; transport infrastructure resilience has been allowed to decay; solidarity among members towards Russia has collapsed; and so on)
A Russian invasion of Ukraine doesn't matter in itself, but it would serve as a giant advertisement for the renewed need for and value of NATO. Putin's previous aggressiveness towards Ukraine already stirred NATO back into life - stationing troops in its members on Russia's border for the first time. A full scale invasion of Ukraine would make clear that Russian promises are not worth anything (in 1994 the Russian Federation solemnly promised to respect Ukraine's borders and sovereignty). The only thing that can work is military deterrence via membership of a reinvigorated NATO. We should expect previously neutral countries like Sweden and Finland to join; for military spending and preparedness to rise dramatically; and for the reappearance of solidarity in members' foreign policy (for example, Germany dropping its oddly pro-Russian view).
A NATO revival is less than ideal for European countries or the USA, which is why they have previously tried so strenuously to avoid it: there are many other things they would rather spend their money and political attention on. But that doesn't make it a win for Russia. Whatever freedom of movement Russia currently enjoys will be sharply constrained. Russia will be surrounded by a heavily armed alliance that also takes steps to isolate and contain Russia's economic and other relations to the world (as they did to the Soviet Union). This outcome is very much not in Russia's interests. Indeed it is the very thing Putin claims his foreign policy is meant to prevent.
4. Good for Putin?
The major problem with the realpolitik approach to international relations that I have been pursuing here is that it neglects the gap between the geopolitical interests of countries and the domestic political interests of rulers. The fact that invading Ukraine will be pretty obviously bad for Russia's interests does not mean that it will be bad for Putin's interests (especially in the short-term). Since Putin is the one who will be making the decision its badness for Russia is somewhat irrelevant to whether the invasion will happen.
Tyrants care about their own interests (staying in power and enjoying the fruits of power), and they use their control over their country's resources to advance those interests. In particular, they are willing to make gambles with their subjects' lives and future in order to achieve their own short-term interests (see further). From Putin's perspective the revival of NATO is actually as a good thing. His oil powered klepto-economy has been shrinking since 2013, and with it the promise of prosperity on which the legitimacy of his regime was founded. Political opposition has strengthened and he has had to move several rungs up the authoritarian ladder from the pseudo-democracy of managed elections to the nakedly violent suppression of dissent. Putin's regime can survive this, of course, but a republic of fear is much less profitable and more dangerous for its rulers (as tyrants like Ceaușescu and Qaddafi discovered).
In this situation a burst of national solidarity would be a great help in rebuilding Putin's stock of legitimacy. Putin has previously generated such bursts with military adventures and opportunism in Georgia, Crimea, and Syria. But solidarity generated by triumph turns out to be short-lived - people soon turn back to their dissatisfactions. A longer term generator of national solidarity is a shared belief in an existential foreign threat. Hence, the revival of a rearmed NATO surrounding and constraining Russia would actually be beneficial to Putin's domestic political interests. It may be the actual aim that a Russian invasion of Ukraine is intended to achieve.
This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License. Attribution: Thomas R. Wells is a philosopher in The Netherlands
2. The biggest cost to Putin may be the political humiliation of being recognised as an emperor with no clothes. He has shown the world that he presides over a 3rd world state with delusions of importance, with a military that is only powerful enough for terrorising the domestic population.