Just goes to show how the market rules all. Outcome of herd behaviour.
Oil, currency and capital markets in this case. The US doesn't need to add sanctions. The markets are doing the damage to Russia.
Unfortunately, as Putin is also a political pariah, he won't get help from central banks in Japan or the US. And if he gets it from China, he loses face.
Raises the political temperature, of course. Putin is bound to think this is an orchestrated American coup. Whereas a few weeks ago it was seen as a Saudi coup against American shale.