The Russian invasion of Ukraine resulted from two immense strategic blunders, Robert Service says.... It rankles Mr. Putin that Ukraine would seek to join the West—and not merely because he wants it as a satellite state. He also “can’t afford to allow life to a neighboring Slav state which has even a smidgen of democratic development. His Russian people might get dangerous ideas.”... Mr. Service says the key to understanding Mr. Putin is his adamant belief that Russia is “a great global power” and that the Russian sphere of influence should extend to as many of the former Soviet republics...