Ukrainian President Volodymyr Zelenskyy ousted the chief of the General Staff, a day after replacing Ukraine’s top military commander, the latest in a series of major changes to the country’s defense leadership.Major General Ihor Skybyuk will take over from his boss, Lieutenant General Andriy Hnatov, Zelenskyy announced on July 22.The shuffle caps a week of major personnel decisions by Zelenskyy that have roiled military command, as well as at the Defense Ministry, where Defense Minister Mykhaylo Fedorov’s ouster prompted days of public protests.The political swirl comes as Ukrainian troops have battled Russian forces to a near-standstill along the 1,100-kilomеter frontline in a war now well into its fifth year.

While Russian troops are grinding forward in places like Kostyantynyvka, their advances are coming at the cost of extraordinary casualties. In some places, Ukraine has eked out small gains, recapturing slivers of territory from Russia.Ukraine has also been buoyed by a medium- and long-range drone campaign that has devastated some Russian logistics – particularly around the occupied peninsula of Crimea – and squeezed Russian oil refineries, causing widespread gasoline shortages.Credit for the drone campaign -- and for Ukraine’s rapid embrace of new technology and tactics -- has gone in large part to Fedorov, a tech-minded whiz-kid who was seen as a break from old-school military thinking.