‘The four camps of congressional foreign policy suggest different readings on the transatlantic alliance. From a liberal universalist perspective, NATO is not just a political and military alliance focusing on collective defence, but rather a collective security cooperation based on shared values. A pragmatic liberal argument views NATO as an institution where allies’ interests and values can be aligned, whereas a prudential realist understanding highlights the alliance’s role in pursuing US interests in accordance with US values. Lastly, from a strict realist perspective, NATO is the contemporary embodiment of an American sphere of interest in Europe.’