Six years of war, some 50 million dead, and then more than four decades of Communist control of half of Europe. If you intend to argue that Patrick Buchanan’s book, The Unnecessary War, is mistaken—that the Second World War was indeed a necessary war—then you must argue that, if we hadn’t fought, the history of the world would have been even worse.

Today on Uncommon Knowledge, Victor Davis Hanson and Christopher Hitchens do just that.