The West should've "intervened" and helped establish actual democracy back in the early 90s instead of celebrating their Cold War victory and the misery of their former enemy. Not intervene in the sense of bombing, of course, but in terms of welcoming Russia to the international community and helping get the economy and political processes back on track. Instead they rooted for a corrupt Yeltsin regime while providing little actual cooperation. Too late for that now. IMO while accusing "America" of causing trouble is ludicrous, Western Russophobia and reluctance to engage productively with a 'new Russia' in the 90s does have its share of blame in the state of affairs now.
Otherwise, there's also the historical experience. There was a Western intervention during the Civil War... didn't go very far either.
http://en.wikipedia.org/wiki/Allied_...sian_Civil_War