Just putting this out there: this will not be WWIII. Russia is weakening globally. Their window is closing. Their population is old and shrinking, their economy is a one trick pony based on energy that is being phased out over the next 5 decades. The fact that they have to invade Ukraine to secure it should tell the world how pathetic their country has become as in their eyes, Ukraine should be as dependent on Russia as Belarus currently is.
This is a continuance of the Cold War, and will end in Russia’s downfall. Look for major investment in Poland, the Baltic countries and Turkey from Western powers in order to push them into regional supremacy, and Russia will falter and decline.