Saturday, I posted on the new Ukrainian offensive in Kharkiv Oblast that has liberated several hundred square miles of territory and threatens to unravel the entire Russian invasion; see Russia’s Disaster in Kharkiv Turns Into an Avalanche of Failure as Ukraine’s Army Advances Without Opposition.The main effort in yesterday’s report was Kupiansk, a critical rail and highway node on the Oskil river. That city is firmly in Ukrainian hands. As I noted yesterday, this places the main railroad line from Russian forces in Ukraine to Russia within range of Ukrainian tube artillery.The Ukrainian offensive in Kharkiv Oblast shows some signs...