Historian Mark Calney presents a history of the Crusades, not as a religious phenomenon but as a geopolitical strategy of empire which served as the "Clash of Civilizations" doctrine underlying 20th century British geopolitics.

Other historical writings by Mark Calney can be accessed here:
http://patriot-project.weebly.com/mark-calney.html#.XB7h9_lKiUl