How would that be political suicide? It's an dictatorship, there is no working opposition, no antiwar movement, anyone can be shut down very quickly.

It's only economical suicide if the West makes it so, which it most probably would not - and then there is the question if that would be enough. What if China is able to provide whatever the West would not. Moreover, Russia has close to no debt and high currency reseerves. It is true that it mostly sells oil, gas and minerals, but there are enough buyers for that.

In short, maybe their calclulus is very different to ours.