Do you know about the Red Scare? It‘s the systematic negative propaganda towards anything questioning the capitalist system that underpins the US-American existence. And that‘s usually Communism, as that‘s the system in direct opposition to Capitalism.
The knee jerk reaction your dad (but you also, up there) showed is a result of that. One hardly can escape that, as it‘s part of the lived reality.
However, it‘s just that, propaganda. Once you start to realize that, you can take steps to see through it. Here Trump is invoking the same boogeyman to vilify his opposition, even tho it‘s likely not even communist or socialist, but just against the capitalist oligarchy.
(Simplified) Communism is a stateless society, where the economic basis of class differences has been overcome. Socialism is one step towards that, it‘s the situation after the means of production, but also stuff like housing have been socialized.
Class difference refers to the contradiction between the exploited working class (any wage laborer, not able to live off of their wealth alone) and the exploiting owning class, the Capitalists (owning the means if production and the land)
You missed to make any kind of argument. The substance of my commentary is independent from the instance my account is on.