You are making a great point that seems to always be ignored. The RCC is a politically driven entity. It does all kinds of hypocritical things because it always wants to maintain its image as "the official" Christian church as well as maintaining access to the highest levels of government. We see this play out with questionable membership numbers that serve to inflate its size and thus influence. However those numbers really don't mean a lot if members are excommunicating themselves without even knowing it.
In both instances you note we see how the political plays a paramount role. Obviously with Hitler he's not a member and with Kennedy a politician in good standing with the media he is a member. In Kennedy's case having a high profile funeral serves to promote the "official" Christian church image. The uninformed don't think of these things, rather they are influenced by image.
The point to be learned isn't how to "pick on the RCC" but why Evangelical Christians should never trust it as an ally. The RCC will do whatever it needs to maintain its perceived status and power, hypocrisy be damned. It seems pretty obvious to me that the war on Christianity is heating up with SSAD (same sex attraction disorder) Marriage the latest tool to ultimately bring churches under state control. As this happens we will be worshiping in house churches just as our Brothers and Sisters in Christ are doing now in closed countries. I expect the RCC will find some accommodation with the state so they don't have to.
Yet as said, when men like Teddy K are treated as members even in death, then it interprets canon law (see here on canon law and Kennedy) and teaches quite nominal RCs are still members, though Chavez (who also recvd. a RC funeral) was worse.