The most obvious point to emerge from this study is that the Popular Front campaign, being nothing more than a means of uniting the political efforts of progressives in a shared and urgent cause, had ample precedents within the history of the British progressive tradition. In the earlier crises of British foreign policy engendered by the Boer War and the First World War, progressives had united across party lines without any need to agonise and without any objection from the leaders of their parties.

A number of the progressives of the Labour left who supported the Popular Front, most conspicuously Brailsford and Trevelyan, had themselves played a role in these earlier united efforts. More than this, however, it is clear that united action and open, inter-party discourse was an established feature of the everyday life of progressives. This is very obvious in the period before the First World War, but it continued to be so in the 1920s and beyond, when men like Cole and Laski came to take their positions of leadership within the progressive milieu.

Placed in this context, the Popular Front campaign presents few difficulties. It can be readily understood by the historian's customary procedure of studying the past of the individuals and institutions involved, and there is no need to have recourse to elaborate theories of Communist manipulation. In the late 1930s, the aims of the Labour and Liberal supporters of the Popular Front partially coincided with those of the Communists.