I highly doubt putin really cares what the west, or for that matter or the rest of the world thinks of him. Putin saw an oppurtunity, and encouraged by a weak America ran by a weak and corrupt government, took it. The Ukraine will fall back under Russian control, and Europe along with the west, are powerless to stop it.
That’s short term thinking. Hitler thought the same regarding the Sudentenland.
Ukraine is presently an independent nation. Putin steps in it and he will in time regret it.