> How would that be political suicide?

I'm mostly thinking international politics and -projects like Nord Stream 2. But even internally, there are already anti-establishment movements in Russia. Unpopular military intervention might be grist to the mill for them. I don't think Putin wants to risk a situation like in Belarus a few months ago. It's easier to govern if the people don't openly disapprove of you, even in a dictatorship.

> It's only economical suicide if the West makes it so, which it most probably would not

I remember plans about excluding Russia from SWIFT. I don't know if that is still on the table.