Of interest, on an artistic context, is that Welles was given unparalleled artistic control over his work, in the midst of the 'Studio', 'Classical' Hollywood era. Citizen Kane also has quite a lot of contemporary references, such as the 'March Of Time' ['March Of Dimes', I believe] and various others to Hearst.
Welles was only given such artistic freedom for 'Citizen Kane' (Which was nominated for 10 Academy Awards, but won only for 'Best Screenplay'), as the story behind the filming of 'The Magnificient Ambersons' demonstrates.
And as for 'war' context, Citizen Kane pre-dates Pearl Harbour [December 7th.], but by 1941, Lend-Lease had already been in place, as well as other 'initatives' such as the counter-attack of U-Boats and trade embargoes placed upon Japan, so whilst not formally a warring nation, America was being pulled into conflict. (Whether this was willingly or not is another question altogether.)