Of course Putin sent his troops into the Crimea. It's where he keeps his navy. Also it has a Russian speaking population that wants protecting from the fascists who have just seized power in the western part of their badly stitched together country. The Western leaders aren't really shocked at any of this and it's hypocritical of them to pretend they are. It should be possible-and it would be if they weren't such babies- for them to sit down with Putin and talk things through to a mutually satisfactory conclusion. Did they enjoy the Cold War so very much that they want to bring it back?