Theres this terrible fear and paranoia of the country suddenly becoming communist or being taken over by the communists? Why and where did this fear originate?
Whilst more can always be sad on the matter, specifically with regards to the origins of America's Communist antagonism following the Bolshevik Revolution of 1917, you might find this thread on the post-WW2 situation most illuminating. In it, u/Kochevnik81, u/CapriciousCupofTea and myself offer explanations from various perspectives (and with different evidence) as to why pure ideological "Communism" might not have been the simple reason why American Presidents were so hostile towards the USSR.