In light of the dissent between the Trump administration and the May government on diplomatic philosophies，the Anglo-American special relationship is put to another test at this point of history. The growing conflicts in terms of global governance has increased the embarrassment in dealing with the bilateral political relations of the two countries. The relative decline of the British power in relation to that of the US makes the special relationship increasingly asymmetrical. Meanwhile，Brexit also impales the UK on the horns of a dilemma where it has to take side between the US and the EU in some cases，thus adding uncertainty to its further trade agreement with the US. Nonetheless，the cooperation between the UK and the US remains close and effective. They still manage to act in concert to deal with both traditional and non-traditional security threats to a large extent.