Did I hear my dreaded name invoked?
[Glenn Anders doth appear in the scratch of a match.]
Thanks, Hadji, for giving us Christopher Welles' seventh birthday present!
As to your questions, where do I start?
I suppose, with the truism that the rebels of one generation tend to become the reactionaries of a subsequent period.
A case in point is John dos Passos, who undoubtedly would have been an influence on young Orson Welles. In the 1920's and 1930's he was one of America's most important novelists -- right up there with Ernest Hemingway and James T. Farrell [who?] -- a strong cultural influence on FDR's New Deal. His magnum opus, USA, an experimental trilogy covering the history of America from the Spanish American War to the Great Depression, could serve as a blue print for the first two-thirds of Charles Foster Kane's life in CITIZEN KANE. It even has the device of a "Newsreel" to provide a running journalistic commentary on day by day history of the years covered in the lives of various characters. And there are biographical sketches of the men (mostly) who were moving and shaking the times, including one of William Randolph Hearst, and of course, his actual 1898 dispatch to his artist/correspondent, Fredrick Remington, in Cuba: "Please remain. You furnish the pictures and I'll furnish the war." [But I doubt that the novel can be thought of as anything like the sole origin of Kane's character.]
Strangely enough, by 1945, when Number One (part of another dos Passos trilogy, District of Columbia) was being published in paperback, and Welles was considering it for a cautionary dramatization on This Is My Best, dos Passos was becoming profoundly disillusioned with the Popular Front politics and milieux he had been such a part of. He came to think of FDR as a usurper of power, and the works of the last fifteen years of his life were quite conservative, increasingly bitter. If you are not familiar with dos Passos, I would suggest The Great Days and Mid Century as later historical novels, similar in form, but different in spirit, to contrast with 42nd Parallel, 1919, and The Big Money (the three volumes of USA).
In the last part of his life, dos Passos became like a tough love version of Charlie Kane.
That brings us to Walt Disney and Orson Welles, and their participation in The Society of Independent Motion Picture Producers, which I've brought up here before.
In 1942, beginning a crusade which led to the Supreme Court decree separating the Studios from their theater chains, in 1948, Charles Chaplin, Walt Disney, Samuel Goldwyn, Alexander Korda, Miss Mary Pickford, David O. Selznick, Walter F. Wanger and Orson Welles formed the above organization, issuing a proclamation rather like Charles Foster Kane's "Statement of Principles." Among these individuals were some of most creative artists of the time, and they wanted to break the economic hold of the Big Studios, which they felt stood in the way of their artistic freedom. They had produced great landmarks, and would continue to do so, and the organization continued to exist, and even function, for many years, but the founders gradually drifted away. A few like Chaplin and Welles never lost their desire for that artistic freedom, nor their anti-fascist convictions, but others made their peace. Walt Disney, for instance, prospered in the new reactionary climate of the 1950's, and as you note, Hadji, became one of the arch conservatives of Hollywood.
As I've suggested when bringing up the little commented upon Society of Independent Motion Picture Producers before, Welles' membership could not have helped his career after his Mercury Theater Unit was slashed from his control in the very year he helped form the Society.
Still, as late as 1945, he might have entertained the idea of an artistic collaboration with Walt and his wonderful cartoon factory.
If you want more information, there is a quite handsome website devoted to the Society:
BTW: if you can find the original "trashy" cover art for Number One, or that of other similar paperback editions from those years, buy them all up.