Why do US cons call opponents "Communist", "Socialist", "Fascist", etc., without knowing what these words mean?

It's just a fear mongering technique they've been using since the1950's to pump up the ire of their base.

They use those code words in a vain attempt to smear anyone or idea that disagrees with the party's dogma.

The reason it now occurs on a near daily basis is not so much to incite fear amongst their ranks to get them to vote, but out of fear because as time passes there are fewer and fewer people who agree with them.

Observing behavior.

This is funny coming from someone who cant even use the word conservative.

Liberals cannot handle the truth. In the US liberals are the same as socialists.

Liberals use the word Liberal when in the classical definition they are anythign but that.

public schools have failed them.

And there is nothing to "covet" in any Collectivist regime. Except all the "Decadent Capitalist" goodies the senior party memebers have. Because you own little to nothing by law.

Anything that is bad, aka liberal, to them can be tarred with any brush. Their logic goes: All liberals fall into the category of things that are bad, all things that are bad fall into the category of liberal. Therefore liberals to them are socialists, communists, fascists, statuses, neo-Nazis, racists, plantation owners, paedophiles, crack addicts, pacifists, war mongers, traitors, psychopaths, lazy bums, hippies etc. Words are meaningless to a conservative, unless it has a negative connotation and can therefore be used to describe a liberal.

You assume too much.