Patriotic Socialism, or PatSoc in short, is not a real thing, but libtards think it is for some reason. It emerged as a libtard pejorative against the most basic Marxist-Leninist principle of 'Socialist Patriotism.' 'Socialist patriotism' is a core socialist value [1] which can literally be found in the textbooks issued to elementary school children in every Communist state in history.
p.380 Chatper 17, part 2: "Cosmopolitism and Not Patriotism Is the Ideology of the Imperialist Bourgeoisie"