*Except around 15-20% of Ukrainian nationals are ethnically Russian and probably do want to be liberated, especially since they've undergone years of persecution by a both a Western-backed government and neo-Nazi militias, had their homes bombed out and loved ones killed.
That doesn't justify a Russian invasion. But the US and UK have invaded countries on much lesser pretexts.
It's complicated*
I disagree. It's not complicated at all.
It's absolutely unacceptable to invade a democratic country.
Understanding the Russian perspective is important as is the historical context, but nothing makes this right even if 20% of the population "probably" support Russia (something I've found difficult to verify given that ethnicity and support for Putin are not exclusive relationships).
Russia is the worlds largest country by a considerable margin and the idea they need more land mass to consolidate their security is frankly ridiculous.
Putin wants Ukraine because he believes it's rightfully "his" regardless of the views of the people.
He's a bully steeped in values and an ideology that's decades (centuries) out of date.
Does that mean the West hadn't made mistakes? Hell no but it's not a reason to denounce what's happening in Ukraine and call it what it is. An invasion by a megalomaniac dictator.