Yes, Russia has the raw power to defeat Ukraine in a full-scale war. But the cost of that victory could be too high for Russia to pay. But would Russia logistics be able to support that war? And I wonder if Russia could afford to wreck their military to achieve that win.
Russia's military, like its population, is more than triple the size of Ukraine's. But should Putin order an invasion, he would not find it as easy as in 2014, when Russian special forces and local irregular militias seized control of Crimea and much of Ukraine's border with Russia without much resistance.
Sure.
Russia had unique and fleeting advantages to seize Crimea in early 2014, and even a half year later found that seizing all of the eastern Donbas was beyond the capacity of what Russia was willing to do.
Remember, Russia didn't try to take the Donbas when Ukraine was too disorganized to resist. Was it beyond Russia's capability to do that while taking Crimea? We see Russian advanced weapons, but the reality is that thin veneer runs out fast in a large war and Russia is back to 20th century mass.
And after 7 years of Ukraine rebuilding their ability to fight, Russia would have to apply more of its limited forces to hammer Ukraine. Don't let Russia's World War II reputation obscure the fact that Russia is casualty averse now.
This author, too, questions Russian willingness to endure casualties.
Still, if Russia can scrape up a large enough force, and if Russia can sustain that force long enough, and if Russia is willing to endure the casualties to fight that long--big "ifs"--Russia can win a lengthy war against Ukraine.
Ukraine could change that over time. Smaller countries can be more effective than larger neighbors with lots of defense needs other than the small target country.
But the problem is that Ukraine is not making the effort to be far less corrupt than Russia to be more effective. As long as Ukraine is as corrupt as Russia, Ukraine will be a smaller and weaker version of Russia.
And in the short term, America isn't confident that Russian claims to move troops back to their home bases can be believed.
Do either Russia or Ukraine want to expend the effort to win?
UPDATE: I heard George Friedman explain that Russia did not intend to invade Ukraine because its troops were positioned in the wrong places. Which I did not know from media reports. But I agree with his point that Russia really can't conquer Ukraine. My discussions of Russian offensive options have agreed with that.