This is a revised look at the classic military publication “The Defence of Duffer’s Drift” originally written by the British Army Officer, Sir Ernest Dunlop Swinton in 1904. In this version of the classic tale, the operation occurs during the Russo-Ukrainian War with 21st century equipment and the added elements of chemical warfare. This was written by a US Army Chemical Officer, for Chemical Officers and appropriately utilizes US Military/US Army/CBRN jargon.