Russian stocks and currency are sliding this morning, not helped by this announcement. Of course, Putin has already put pressure on major US companies such as MSFT, IBM, MCD, INTC, AMD, and car manufacturers. And as far as "isolation" - the signing of a 5-year trade agreement with Iran would suggest there are still plenty of nations willing to work with Putin.
It seems Putin is comiong through with his promise:
And Russia issued a statement that US will feel 'tangible losses' from 'destructive, myopic' sanctions.
We have repeatedly spoken about the illegitimacy and groundlessness of the US sanctions against Russia.