In sum, the sequence describes the decline of British power during the twentieth century, a decline attributed by the author to a change in the values of Britain's governing élite from the late eighteenth century, and one which was encouraged by evangelical and non-conformist Christianity. Barnett claims that the statesmen of the eighteenth century were men "hard of mind and hard of will" who regarded "national power as the essential foundation of national independence; commercial wealth as a means to power; and war as among the means to all three". Furthermore, they regarded it as "natural and inevitable that nations should be engaged in a ceaseless struggle for survival, prosperity and predominance". The British national character, Barnett argues, underwent a profound moral revolution in the nineteenth century which came to have a deep effect on British foreign policy; foreign policy was now to be conducted in a reverence of highly ethical standards rather than an "expedient and opportunist pursuit of England's interests". Barnett came to this conclusion by beginning "with a colour-coded flow-chart which logically traced back step by step to their origins the chains of causation of all the 'total-strategic' factors in Britain's plight in 1940-1941: political, military, economic, technological. These various chains eventually converged on a common primary cause: a mutation in the values – indeed the very character – of the British governing classes which began in the early nineteenth century. This mutation supplied the starting-point of my narrative, and thereafter, in Enoch Powell's words in his review, was my 'guiding and interpretative thread through the events of the twenty inter-war years'."