An announcement in the Detroit Free Press on November 28, 1943, page 50, read:

Wyndham Lewis to Lecture
Novelist, poet, critic, philosopher and painter, Wyndham Lewis will lecture on ‘The Frontiers of Art” Tuesday evening in the Detroit Institute of Arts, developing his belief that in the world of the future national or nationalist cultures must disappear.  He sees in the United States a preview of a forthcoming international “cultural melting pot.”
Lewis will remain at Assumption College, Windsor, throughout December to complete a series of lectures, later to be published in book form, on the duality at the root of American political life.

McLuhan was open about his intellectual debt, or debts, to Wyndham Lewis.  One of these is clear in a passage from the beginning of this lecture:

The day of closed systems, of watertight group-consciousness, are at an end. With television tomorrow causing us to be physically present (in our living room, with one of its walls a screen for long distance projections) at contemporaneous happenings all over the earth: with the vast development in the immediate future  of airtravel, which will abolish distance, and strangeness: with the cultural standardisation which has already resulted, and must in the future increasingly result, from this — with all these and many other technological devices expanding our horizons and making a nonsense of the old-fashioned partitions and locked doors of our earthly habitat (…) national or nationalist (…) cultures must disappear.¹

In fact in a 1929 essay, “A World Art and Tradition”, he had already observed that “the Earth has become one place, instead of a romantic tribal patchwork of places.”

Further strong influences on McLuhan from Lewis included his blasting style, his use and abuse of masks, his delineations of human types, his concern with varieties of space and time, his insights into nihilism² and his fascination with the “magnetic city”, especially its warp of “the human dimension”³. Many of these McLuhan would develop in reverse, probing how to counteract or how to preserve when Lewis saw an unstoppable transformative force at work. Across such differences, however, above all in regard to religion, Lewis gave McLuhan a model for the use and development of his childish eye which, like Lewis’, could see very well that the emperor had no clothes.