What I mean is that if the west imposed hard sanctions, i.e. stopped purchasing oil & gas, the Russian government would lose 75%-80% of it's revenues. That would soon bring any government to its knees. However, such sanctions would also inflict so much pain on Europe, that I don't believe anything of that nature will happen. Which is why I believe any sanctions will be purely symbolic so that the west can save face and claim that "we" are doing something.
I agree with you that the fact that Russia has a powerful, nuclear-armed military makes it a factor in the west's decision-making. At the same time, I don't think it's a "real" factor, because the military option would be instantly dismissed as reckless.