In his recent book Churchill, Hitler, and "The Unnecessary War": How Britain Lost Its Empire and the West Lost the World, Patrick Buchanan argues, as described in the Amazon blurb:
Were World Wars I and II—which can now be seen as a thirty-year paroxysm of slaughter and destruction—inevitable? Were they necessary wars? Were the bloodiest and most devastating conflicts ever suffered by mankind fated by forces beyond men’s control? Or were they products of calamitous failures of judgment? In this monumental and provocative history, Patrick Buchanan makes the case that, if not for the blunders of British statesmen—Winston Churchill first among them—the horrors of two world wars and the Holocaust might have been avoided and the British Empire might never have collapsed into ruins. Half a century of murderous oppression of scores of millions under the iron boot of Communist tyranny might never have happened, and Europe’s central role in world affairs might have been sustained for many generations.
I haven't read the book, and am unlikely to put significant time to anything by Buchanan, but I found the discussion in Peter Robinson's Uncommon Knowledge podcast, with Christopher Hitchens and Victor David Hanson, to be quite illuminating:
I actually listened to it in podcast form, though that entry doesn't appear to be in the podcast feed any longer. However, you can subscribe to the Uncommon Knowledge audio podcast or video podcast for Uncommon Knowledge using those URLs (it's darn difficult to find those URLs, too!)
Finally, you can find it chopped into several segments at this site.
I do all the legwork so you don't have to!