Putin's war against Ukraine is already a nuclear war.   Although he has not pushed the nuclear button, Putin and his propagandists have used Russia's nuclear arsenal extensively to try to intimidate Ukraine and  -- in particular -- the West.  Threats of nuclear war have been fast and furious, with Russian TV commentators expressing outright glee at the prospect of nuclear annihilation of the UK, the US and other Western targets.  The Putin regime has discarded limits that even the USSR had in place on the inadvisability of nuclear threats.  If Putin's nuclear threats succeed in Ukraine, we can expect him deploy such terror tactics against his next target.   Western leaders must tred carefully, but not succumb to Putin's nuclear blackmail.