???....what colonization?
Joke because the US is starioning units there on rotation
To add to the irony of it, its doing so on invitation of a social-conservative government that hates Russia and leftist progressivism alike.
From the Russian perspective, they'll need to act relatively soon to blunt the impact of the coming demographic and economic crisis.
Russia is basically a glorified petro-state with too much of its capital tied in the hands of a few oligarchs who largely use funds to maintain their power and influence rather than using it to foster internal economic development.
There is another reason for this. Russian military prowess is slowly losing distance technology wise from the world's current leaders. Note how the vast majority of Russian hardware was built, or in case of newest pieces, at least planned and somewhat prototyped in the Soviet Union and is now being finished off... consider the time it took them to get it done, people in USA complain about F-35, but consider that PAK-FA, aka Su-57 aka Russia's 5th gen fighter is the result of a project started in late 80's as an answer to US Advanced Tactical Fighter program, which has resulted in F-22. But F-22 is in service since quite a long time, while SU-57 is still being developed, with about a dozen planes built, 2 of them serial, its first flight over a decade ago, official introduction few months ago, and its always just so close to being finished and having mass scale introduction into the air force, current ambition being 78 planes, we'll see how downscaled that gets by budget limitations.
Same story with Object 148 aka T-14 aka Armata - an implementation of some nice tech developed in work for Object 195 which was also started in the 80's, worked on until prototype stage in late 2000's and then cancelled. There were grand plans for over 2k of them in 2020, but so far there are only dozens semi-prototypes built, and slow bugfixing is being done with them, yet older T-72/T-90 variants are still being modernized, with clear intent to not replace them anytime soon.
Both of these are also being aggressively offered for export even to not so closely allied but merely friendly countries like Egypt and Algeria, showing the clear desperation for extra funding.
Cam you see the pattern? Despite trying hard with its 4% GDP military spending (while for many NATO countries mere 2% is apparently too ambitious, and USA stands at around 3.5%), and squeezing the industrial, material and technological leftovers of Soviet superpower level military ambitions for everything they are worth, they are struggling really hard to keep up, and inevitably falling behind. Much slower than expected due to these extreme efforts, but they are. What are they going to scare EU with when these thousands of modernized T-72's and their variants are going to be considered as obsolete as T-55's are now? They certainly won't have thousands of T-14's to replace them, because for that they would need to be well into building them already. They may have a few hundreds, maybe around a thousand of them at most, and they will need to split them between the west, the south ("dear allies" and possible rogue republics) and the east (very big, mean and hungry dragon). And what will they be working to supplement the Armata's with? They won't have an ex-soviet program to take as groundwork for it anymore, they will have to do that from scratch, and pay for it, which you can see how they struggle with even for building the things already.
By the size of population and economy, Russia is going to slowly trend to being merely one step, and in time a small step, above Turkey. Which is just one NATO country, with a big but not particularly advanced army, and decent, but not bleeding edge technologically defense industry. Also with nukes. But even Pakistan has nukes, and they are a step below that.
Hence, if Russia wants to throw its weight around in the west (they already have to play defensively in the east, but the south is not doing any better than them) and not get laughed out, it has to be within 10-20 years, perhaps 30 at most, while its military still can punch above its economic weight, because that advantage is decaying with every decade, and it has lost 3 decades worth of it already.