Putin's choices
...German tactics were built on Russian deniability of any direct involvement. The diplomatic game was based on the pretense that both sides were not much more than concerned neighbors, that Russia was not part of the conflict.
But indirect involvement was not enough to hold territory in Ukraine. That's why Putin either had to accept defeat or to step up his efforts and end the pretense of Russian non-involvement. He chose the latter.
Putin did so knowing that this would lead to more Western sanctions, more costs for Russia.
But he may have gambled that the West would not massively increase sanctions, as the appetite for conflict with Russia is low in many European countries, especially in Western Europe. It is also possible that he may even be ready to accept economic divorce with the West.
The West has tried everything to convince Putin to step back from the brink of open war in Ukraine. But it has not worked. The success of the Ukrainian army on the ground has forced Russia to make a choice between ending efforts to bring back Ukraine under Moscow's control -- or moving to open war. Putin had to leave the fog and make a move.
The German approach now looks like a failure, but it was worth trying nevertheless. It might have worked. Diplomatic efforts may also have kept Russian involvement to a minimum in the last few months -- they may have caused Putin to keep a low profile, thus allowing Kiev to recover and win back territory...
http://edition.cnn.com/2014/08/29/opini ... ?hpt=hp_c1