The energy crisis of the 1970s marked a crucial global transformation. Higher oil prices caused the greatest peacetime transfer of wealth and the largest single infusion of liquid capital into the global economy in history. Much changed after, but oil diplomacy also emerged out of the previous era. Since 1945, foreign policy and oil security had revolved around the well-being of first the domestic and then the global economy. A sense of impending danger to that well-being set the contours of policy and relations with different actors in the oil-rich Persian Gulf. American leaders saw a world in potential disarray and their concern over supply and price stability led the nation to greatly expand its military power in that region.