A squad of Ukrainian “kamikaze ground robots” airdropped behind enemy lines have taken out 3,000 Russian soldiers and reclaimed 48 square miles of occupied territory in Donetsk, officials announced. The secretive mission, dubbed “Operation Vivaldi,” began in May and wrapped up last week, when the Third Army Corps of the Ukraine’s Armed Forces made details of the feat public. “An historic moment,” it boasted on Telegram Thursday. “The Third Army Corps has begun a new stage of the war with the landing of ground robots.” The operation recaptured five villages and three settlements in the contested region of Donetsk in...