As others mentioned, you are vastly overestimating the literacy rate of average people. People talk about 95%+ literacy rates in developed countries and this is true in that the majority of people recognize basic words, but this level of emergent or basic literacy is insufficient in the context of political understanding. In most of the west, about 50% of the populace is below level 3 literacy per piaac definitions (see link below).
Comparison of some developed countries WRT literacy levels https://www.conferenceboard.ca/hcp/adlt-lowlit-aspx/
Definitions of piaac literacy levels (near the bottom, press the plus) - note the details of the definitions, effectively level 4-5 literacy is required for meaningful political understanding, let alone analysis https://nces.ed.gov/surveys/piaac/measure.asp
Blackshirts and reds is an awesome polemic. It’s exciting to read and very engaging. The assassination of Julius Caesar may also be worth suggesting as a starting point for some kinds of people because it is about a time and place far away, and so is less ideologically threatening than the story of the allies subordinating nazis into western anticommunist terrorism.