Salah ad-Din, Yusuf ibn Ayyub
Alexander the Great
Sir Arthur Wellesley, Duke of Wellington
Akbar the Great
Roessler's first major contribution to Soviet intelligence came in May 1941 when he was able to deliver details of Operation Barbarossa, Germany's impending invasion of the Soviet Union. Following the invasion, in June 1941, Lucy was regarded as a VYRDO source, i.e. of the highest importance, and to be transmitted immediately. Over the next two years "Lucy" was able to supply the Soviets with high grade military intelligence. During the autumn of 1942, "Lucy" provided the Soviets with detailed information about Case Blue, the German operations against Stalingrad and the Caucasus; during this period decisions taken in Berlin were arriving in Moscow on average within a ten-hour period; on one occasion in just six hours, not much longer than it took to reach German front line units. Roessler, and Rado's network, particularly Allan Foote, Rado's main radio operator, were prepared to work flat out to maintain the speed and flow of the information. At the peak of its operation, Rado's network was enciphering and sending several hundred messages per month, many of these from "Lucy". Meanwhile Roessler alone had to do all the receiving, decoding and evaluating of the "Lucy" messages before passing them on; for him during this period it became a full-time operation. In the summer of 1943, the culmination of "Lucy's" success came in transmitting the details of Germany's plans for Operation Zitadelle, a planned summer offensive against the Kursk salient, which became a strategic defeat for the German army—the Battle of Kursk gave the Red Army the initiative on the eastern front for the remainder of the war.
“To do evil, a human being must first of all believe that what he’s doing is good" - Solzhenitsyn
"...with the terrorists, you have to take out their families." - Donald Trump
That being said there is overwhelming evidence that the atomic bombings figured more prominently in forcing the immediate Japanese capitulation. It is incredibly unlikely that a swift unconditional Japanese surrender would have been forthcoming in mid August just because of the loss of Manchukuo-Manchuria and Korea. Devastating yes but it did not directly imperil the Home Islands nor did it deflect from the possibility of a terrible resistance that might minimize the peace conditions. With the atomic bombings it completed the strategic picture of total and utter defeat.
Sorry just my peeve.