He didn't have a justification like 9/11? By that you mean an emotive attack on his civilians, I guess? I beg to differ, soyim. They have had several incidents like that. The ongoing war in the Donbass has been very, very emotive to our Russian friends. Just because the atrocities there haven't been plastered all over our media it doesn't mean that they aren't ubiquitous in the Russian speaking world. People want redress for these injustices.
Russians have all seen the picture of Polina Sladkaya, the first child casualty of the Donbass rebellion. Killed by Ukie artillery by the way, the first of allegedly a hundred children to die in such a manner. Google (in my country at least) seems to be cleansed of results for her periodically, I have no idea why. If you google her at the time I am writing this you can find a commemorative tweet and a single image on google images related to her. The rest are just random women. She wasn't so hard to find a couple of years ago...
There is the famous video of the Azov regiment crucifying a civilian for aiding the separatists. it is very upsetting. A lot of people mistakenly call it fake but they are mixing it up with a different fake report of a 5 year old boy getting crucified. It is still easy to find as I am typing this, in this thread and even on reddit. The Azov boys are also famous for mass-rapes as well, which you can also find reports of quite easily. They have never been brought to justice.
The Odessa Massacre of 2014 is also a bit of a sore spot. Dozens of Russian counter-protesters (opposed to the Euromaidan movement) were chased into a building, trapped inside and burned alive. The Ukies filmed it all while singing and cheering.
Look, I'm not saying that war is good. I'm not saying that Ukrainian civilians should suffer. I'm saying that there are surely plenty of ethnic Russians feeling just as worked up about this as we were about 9/11.
I'm also saying rate this post informative or your mother will die in her sleep tonight.