It's a pretty safe bet that Comrade Woody's list of New Years resolutions for 1941 contained nothing whatsoever about beating fascism.
You nailed it! Until Hitler broke his nonagression pact with Stalin & invaded the USSR in June 1941, Guthrie was a good little commie like all the others who chanted “The Yanks Are Not Coming!” & preached strict isolationism.
After June 22nd, the commies in America began chanting “The Yanks Are Not Coming Too Late!!” and the alliance with “our heroic Soviet ally” was a matter of Party discipline while Comrade Woody inscribed his guitar with “This Machine Kills Fascists!” and hit the road for the war effort.
Since 1967 Woody Guthrie has been First Peoples’ Commissar of Soviet Hell.
By 1943, Guthrie had a "This Machine Kills Fascists" sticker on the front of his guitar. In 1945, he switched to a Gibson Southern Jumbo and put a larger sticker with the same message on that guitar.
Guthrie viewed freedom vs. fascism as the ultimate battle.
As for socialism or communism, that may be another matter (although Guthrie wrote several anti-Hitler songs).