Do you know about what Victoria Nuland (leaked intercepted tapes), Senator John McCain, Senator Lindsay Graham, Hunter Biden, CIA John Brennan, etc. did in Ukraine?
Zelenskyy ran on peace with Russia, but his puppet masters in Washington would never have allowed that.
So, by late-2021, do you know that Zelenskyy had a sub-28% approval rating from his own population because he threatened to acquire nuclear weapons, threatened to join NATO, join the EU (comes with military connections also, BTW), take back Crimea and the entirety of the Donbas, etc.? His population mostly wanted Austria-style neutrality but he was being strung along by the US because we wanted to turn it into a battering ram against Russia.
So, Russia acted pre-emptively. Heck, by our logic, this war is more justified than the Invasion of Iraq in 2003.
You have to look at the entire political situation in Ukraine, starting at least since 2003-4. And, especially 2014 and the US-backed putsch that took place that year.