KYIV — As Russia steps up airstrikes and once again advances on the battlefield in Ukraine more than two years into its bloody invasion, there is no end to the fighting in sight. And President Volodymyr Zelensky’s options for what to do next — much less how to win the war — range from bad to worse. Zelensky has said Ukraine will accept nothing less than the return of all its territory, including land that Russia has controlled since 2014. But with the battle lines changing little in the last year, militarily retaking the swaths of east and south Ukraine...
