International is critical to growth but also brings in large volatile risks. Most of the world is not a liberal democracy subject to the rule of law which evolved from a Judeo-Christian ethic.
The fleet of aircraft is very capital intensive and requires constant repairs and upgrading. FedEx cannot take the loss of prestige with a major malfunction or crash. This means you spend spend and spend again.
FedEx will always be exposed to energy price risk. Everything from local trucks to air freighters guzzle energy. Very thirsty business.
FedEx is finding their US labour model to be under siege. Unions and Democratic government/regulators know these jobs cannot be outsourced. Labour will continue to become more expensive and less flexible. FedEx cannot shrink their US market share without declaring capitulation.
George Gutowski writes from a caveat emptor perspective.