"Hence to fight and conquer in all your battles is not supreme excellence; supreme excellence consists in breaking the enemy's resistance without fighting." -Sun tzu, The Art of War And, of course, I think anyone would agree with that. But on the topic of best military leaders... In many respects, Hitler was an exceptional leader: he pulled Germany out of the Great Depression before any other country, he defied the harsh and unfair Versailles Treaty, regained the lands taken from Germany in 1919, and brought back a sense of German national pride. Of course, this is all overshadowed by his brutal treatment of "inferiors". I don't know that he could be considered a great military leader though. His Blitzkrieg warfare was highly successful, but the invasion of Russia... I almost voted for Erwin Rommel, but for the fact that he was defeated. Instead I voted for Douglas MacArthur. Commander of Allied Pacific forces in WWII and of U.N. troops in Korean War. Personally, I think Truman was wrong to fire him.
Afterthought - Chiang Kai-shek was pretty good too. 1926 Northern Expedition unified China, then 1937 opposed the Japanese beyond all expectations. But I think more credit should go to his German high command than to Chiang himself. So perhaps he is one of the best organizers of all time for hiring German officers.
I cannot see how it is not Alexandros. Logistics, Tactical, Organizational, Strategy, Charisma and even personal valour are unequaled from antiquity to present day. 5 of his Generals(each their own master of warfare and leadership) went on to carve out empires that were major players in the near east for the next 250 years. These men and what wound up, a cadre of the the most elite experienced troops the world has ever seen, followed Alexandros beyond all reason. For this, he has the "leader" part of this title locked cold. His military achievements, undefeated, often against ridiculous odds in the short span of 10 or so years(in command) match or exceed all others before(that we know of) and since. He took on the world's superpower of the day and did not leave many white places on the map. Persia was probably at nearly it's height of power(perhaps it was stronger a few decades before). He took it, all of it, from Anatolia to beyond the Nile to the mountains of eastern India and then some in, 10 years. No guns, no tanks. 10 years using swords, arrows, horse and guts. That kind of conquest was unheard of in antiquity. WWII was nearly 6 years for most nations.
Paul Tibbets. Aircraft commander of the Enola Gay vaporized 70,000 people in one second. http://en.wikipedia.org/wiki/Enola_Gay http://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki