I think u make some important points. It is reductive to label all Constructivists, Supremacists and Futurists as reactionary - there were phases and individuals in these movements who may have been revolutionary. However ultimately the movements were reactionary.
DUchamp however was not a movement but an individual worker. He was championed by the revolutionary SUrrealists - and broke with the fourth dimension in moving onto an n-dimensional theory in the Green Book - notes on the Large Glass. In this way he showed more sense that reactionary collaboraters to mass-murder like Einstein who advocated the ridiculous Euclidean 4th dimensionalism. For sure we can also differentiate between Euclidean 4th diemsnion and non-EUclidean 4th dimension.
Also, Duchamp was not a conceptualist - rahter borgeois art critics recuperated his work as conceptualism. and Whatever the problems with conceptualism we cannot compare it to fascism. BOccioni was a proto-facist (he helped to develop the movement) - conceptualism does not advocate mass murder, as fascism or imperialism does. as erroneous as it is to separate art movements from political ones, it is at times necesary to do so in order to get a different perspective from which to understand a situation (ie to understand a different workers view point).
(following from http://www.accessmylibrary.com/article-1G1-69411772/fourth-dimension-and-futurism.html)
In the opening lines to his 1914 volume Pittura scultura Futuriste: Dinamismo plastico (Plastic Dynamism), Umberto Boccioni announced his desire to transform Italy. Dedicated to "the genius and muscles of my brothers Marinetti, Carra, Russolo," Boccioni's book proclaimed "plastic dynamism" the expression of an "antitraditional and antirational avant-garde that must rejuvenate Italy and the world by exacerbating their spiritual speed."  In his attack on tradition he condemned both the retrograde aesthetic taste of "a democratic public made up of pseudo-intellectuals, anarchists, and socialists" like Enrico Fern, the socialist director of L'Avanti, and the aesthetic preferences of the ultranationalist Enrico Corradini, who had reportedly "dirtied his name" by defending "one of the most mediocre Sunday painters of Verona."  As a supporter of Corradini's Italian Nationalist Association (founded in 1910), Boccioni admired Corradini "for his nationalist
beliefs" but lamented his failure to appreciate the poli tical import of Futurist aesthetics.  In contrast to traditionalists on both the left and right, Boccioni, in Plastic Dynamism, claimed that a "renewal of plastic consciousness" among Italians required opposition to the debilitating effects of "democratic-rationalist education."  Thus, the aesthetic of plastic dynamism propounded in Boccioni's volume was not only "antitraditional and antirational," it was also antidemocratic in its regenerative aims and nationalist in its aspirations.
Although scholars have recognized the antirationalist premises undergirding the Italian Futurists' rejection of parliamentary politics, the integral role of Futurist aesthetics in that polemical project has yet to be elucidated fully. Through an examination of Boccioni's Futurist tract, Plastic Dynamism, and works such as his Unique Forms of Continuity in Space (1913, Fig. 1) and Carlo Carra's Funeral of the Anarchist Galli (1911, Fig. 3), I will explore the Futurists' incorporation of aesthetic theories of time and space into a utopian campaign to transform the consciousness of the Italian citizenry and inaugurate a political revolt against Italy's democratic institutions. By analyzing the role of a theory of the fourth dimension in this highly politicized aesthetic, I will expand on Linda Henderson's important insights regarding the Futurist fusion of the spatial fourth dimension with notions of temporality and intuitive consciousness derived from the
French philosopher Henri Bergson. 
As Henderson has demonstrated, theories of the fourth dimension and related concepts of non-Euclidean geometry were instrumental in overturning the assumption upheld by nineteenth-century positivists that space was limited to the three dimensions described by Euclid. The new geometries undermined positivism and inspired idealist philosophical interpretations that associated the fourth dimension with a higher, mystical reality beyond three-dimensional visual perception. Theosophist Helena P. Blavatsky announced that perception of the infinite, unbounded nature of fourth-dimensional space opened our consciousness to unseen, spiritual realms, while the Russian mystic P. D. Ouspensky claimed that time itself constituted another, spatial dimension and that motion in time was in fact evidence of higher dimensional "virtual volumes." As Henderson noted, Boccioni's allegiance to the theory of temporality developed by Bergson meant that he was particularly
interested in "dynamic" theories of the fourth dimension. Rat her than generating fourth-dimensional form by the motion of a three-dimensional object through space, Henderson argues, Boccioni operated in the reverse process by considering the passage of a higher dimensional form through our space. Boccioni's claim that the spiral was an innately dynamic shape expressive of fourth-dimensional "absolute motion" is interpreted by Henderson as evidence of his awareness of the "hyperspace" philosophy of Howard Hinton, whose book The Fourth Dimension (1904) illustrated a spiral moving through a plane as one of many mental exercises designed to develop a reader's "space sense." Hinton and Ouspensky thought time and motion in three dimensions constituted an illusion to be overcome by nurturing our spatial consciousness; Boccioni, by contrast, "asserted the positive value of time and motion" following the theories of Bergson. Henderson therefore concludes that
theories of the fourth dimension were less integral to Boccioni's aesthetic since Hinton's and Ouspensky's devaluation o f temporality was fundamentally at odds with his Bergsonian precepts.
I will argue that Boccioni did seek to generate fourth-dimensional form through the motion of a three-dimensional object through space, and that his notion of the fourth dimension owed more to his knowledge of the Bergsonian concept of "extensity" than to a reading of Hinton or other "hyperspace" philosophers. Moreover, in contrast to other proponents of the fourth dimension, Boccioni assimilated this spatial concept into the Futurists' highly politicized campaign to renew Italy. The Futurist correlation of the fourth dimension with a Bergsonian spatial-temporal flux made up of "force forms" and "force lines," unfettered by the limitations of three-dimensional space or measured "clock" time, fused with a political program premised on intuition and an antimaterialist call for national regeneration and imperialist expansion. The correlation of imperialism with national renewal was first propounded by the Bergsonian Georges Sorel and developed by his
Italian followers Enrico Corradini and Mario Missiroli; the i mpact of Sorelian thought on the Futurists is well documented by historians such as Gunter Berghaus, Giovanni Lista, and Zeev Sternhell.  I will argue that the fourth-dimensional force lines and force forms emanating from works like Carlo Carra's Funeral of the Anarchist Galli (1911) or Boccioni's Unique Forms of Continuity in Space (1913) registered not only the artists' intuitive transformation of the self but also a desire to transform the audience who came to view such work and were intended to transmit the Futurist spirit of heroic violence and gendered will-to-power to the Italian public.