Old Chinese saying:
"The beginning of wisdom is to call things by their proper names".
Libertarians consider themselves to be "classical liberals". Adam Smith called himself a liberal, fi.
I think that calling socialists "liberals", in American politics, represents a corruption of language, and a muddling of thought. Especially since the policies of FDR, who may be called the prototypical American "liberal", are 81-68 years old, his could well be considered the conservative positions, at this remove, meaning that those who still put faith in those failed policies are the ones who resist change.
I like these M-W defs for liberal, neither of which apply to the typical American Authoritarian/Collectivist, whether he is a dem or a repub:
b archaic : of or befitting a man of free birth
: broad-minded; especially : not bound by authoritarianism, orthodoxy, or traditional forms
Nobody ever went broke underestimating the intelligence of the American public.
H. L. Mencken