If the question is about the basic conception of a foreign policy agenda, it means basically a set of ruleswhich the U.S. government follows towards allies and opposing countries, policies regarding the U.S. and the U.K. trading is much different than the policies towards Iran for instance.
One famous example is the Monroe Doctrine which basically opposed colonialismin in the Americas -- Although French Guyana is still under French government and the Falkland Islands/Malvinas are still under teh command of the UK.