I believe also that the predominating thought in this war among the generals that plan it is that a shake up to the current status quo was needed. Invading Russia gives Ukraine a bit of leverage, plus it draws away RU troops from the front line so that Ukraine may be able to retake a bit of ground.

Grand Poobah Pooty Putin can only say so many times that he's moving nukes to ready status or whatever until it becomes clear he's not going to use them. Nuking anybody, especially Ukraine, would be a tacit admission to the world that he's losing this war. If he did, NATO would likely get involved presumably because they would consider the fallout drifting over Europe to be an act of war, but a casus belli is a casus belli.

So yeah, I can see NATO countries being ok with a strike inside of Russia now. Makes total sense to me. I'm just surprised it took this long to get there.