Basically, since WWI (which tested the imperial model to destruction), the idea that a small number of empires can divide the rest of the world into spheres of influence has collapsed.
The little countries no longer tolerate being pushed around by the Great Powers.
The Great Powers, of course, don't much like that fact. But they are divided into those who cope with it, and those who continue to deny it.
The old powers of the west mostly read the writing on the wall, and decided to give their colonies varying degrees of independence, in an effort to avoid total rejection. This leaves them with ex-colonies who are still subject to "soft power" influence from their former masters; They are independent but (mostly) friendly, and maintain strong (if no longer exclusive) trade links with the former colonial power.
This was, of course, an imperfect and difficult strategy, and often efforts were made to reimpose colonial rule, or to ignore the rights and voices of smaller nations. The Munich Conference just before (and directly causative of) WWII breaking out in Europe is the classic example of how the old system utterly failed, though the participants had stupidly decided to pretend it still worked. Czechoslovakia wasn't even included in the talks, which were about Czechoslovakia.
Of course, the consequence for the Czechs and Slovaks was dire, but more importantly, so was the consequence for the French, the British, and (ultimately) even for the Germans who had apparently achieved their aims.
Similarly with the Molotov-Ribbentrop pact that divided Eastern Europe between the USSR and the Third Reich, without consideration for the peoples and nations involved. It worked in the short term, but being Hitler's ally ultimately bit Stalin on the arse, and in the long run, both Great Powers ceased to exist, while Poland and the Baltic States became independent nations, and joined both NATO and the EU voluntarily, for the military and economic benefits (respectively).
Putin's epic fail is to see NATO and the EU as old school 'spheres of influence' for Great Powers; This is a fatal error. The USA doesn't control NATO (though Trump is in the process of making the same error as Putin, in thinking that it does); Germany and France don't control the EU, either. Being big and important doesn't imply being in dictatorial control. Indeed, dictatorial control was demonstrated in the C20th to be a route to failure.
Since then, it has been apparent that the C19th concept, of Great Powers who can divide the rest up as they will, is dead. Efforts to do so still occur, but the small countries simply say "fuck you". Vietnam said "fuck you" to France, and then to the USA. Korea said "fuck you" to Japan, and then to the USA and China, leaving nobody happy. East Germany said "fuck you" to Russia, while West Germany was given autonomy by Britain and France in a way that flew in the face of earlier ways of dealing with a defeated foe.
Russia never bothered to learn the lessons of the C20th, and by 1991, this failure had blown up in their face, leaving their efforts to build an empire in Eastern Europe in tatters.
They still haven't learned this lesson.
Cooperation works in the long term. Domination doesn't. If the movie
Braveheart taught us anything (and it didn't), it was that you can take our lives, but you cannae take our freedom. (Also, that there was no bridge involved in the Battle of Stirling Bridge, and that William Wallace's army wore clothes that wouldn't be invented for nearly two centuries, and face paint that hadn't been in vogue for nearly two millennia; But I digress).
It's not hard. But Russians are lazy and backward. Putin's Russia is a C19th imperial power, transported almost unchanged into the C21st, but now with nuclear weapons rather than massed heavy cavalry.
It's an anachronism. And it cannot understand why what it is trying to do in rebuilding its irredentist empire is seen as immoral by the other powers (even China, who at least understands that trade now trumps war), nor how its victims are both willing and able to resist, as they understand that resistance is not only possible, but noble.
Russia had a superb opportunity to join the rest of the world in the C21st, but Putin decided that his personal disappointment at the failure of the Warsaw Pact to maintain Soviet rule, and then the failure of Moscow to even hold the USSR together, required turing back the clock to the 1800s. This is, to quote Captain Edmund Blackadder, the worst decision in military history "since Olaf the Hairy, high chief of all the Vikings, accidentally ordered 80,000 battle helmets with the horns on the
inside".
Patriotic and nationalistic fervour from
@barbos causes him to be enraged by these facts; But facts they remain. If Russia persists with the Putinist strategy of trying to ignore the weight of history, she will be crushed unmorned by it, as were the Austro-Hungarians, the Ottomans, the Japanese Empire, the Third Reich, East Germany, and the USSR.
They can, of course, still fuck things up massively for the rest of the world in the process, if they feel like being pointlessly spiteful. This won't do anything to save them, though; It will just make the survivors that much more keen to piss on their graves.