I think that, in most cases, US commentary does depend on which socialist country is being discussed.  We have no problem with the UK's or most other EU countries' socialism, but the more dictatorial (China, Cuba) are definitely seen in the Leonine light.  
I'll stipulate to the four categories you provide, for the sake of argument (though I reserve the right to later disagree) and reply that the US foreign policy always seems to favor democracy over dictatorship and capitalism over socialism, as if each was homogeneous and, therefor, reducible.  What it lacks in terms of realpolitik it makes up for in dog-whistle talking points and clear (if misguided) foreign policy direction.