As a rule of thumb, militaries around the world want to export their military aircraft to as many friendly countries as possible. Exports are often vital for a country to afford to develop its own extremely expensive military aircraft. Today, there are arguably only two countries that can more or less afford to develop their own aircraft for their own needs without worrying heavily about exportsthe United States and China (Russia no longer fits this category). Here are five aircraft built exclusively for the United States Air Force ( more aircraft like the F-117 Nighthawk could also be added to the list).