OOC: Apparently, we also have to operate under the assumption that not only does Joe Jr survive because Jack gets a court martial, but that he's elected President just like JFK. And, somehow, butterflies lead to RFK living too and getting elected President, and the Kennedys accomplish the amazing feat of getting a third member elected President. (Even though IOTL Ted never wanted to be President, and only ran in 1980 because of a feud with Carter). There's so much wrong here that I won't respond with a DBWI post. I will say that ideas like this are why I'm becoming increasingly uninterested in alternate history....
OOC: Do we really know that Ted "never wanted to be president"? True, he declined to run in both 1972 and 1976, but he must have realized that Chappaquiddick would hurt him both times. By 1980 he may have assumed (wrongly) that sufficient time had passed that it would no longer be such an issue. In any event, if something (in OTL disagreement with Carter's policies) did induce him to run, presumably something else could induce him to run in an alternate timeline. In other words, his reluctance
could be overcome.
I am not assuming, incidentally, that a surviving Joe, Jr. would become president at the same time and in the same way that JFK did in OTL. I am not assuming that he narrowly defeats Nixon in 1960. There are all sorts of other years and all sorts of other ways (including succession from the vice-presidency) during a fairly long period that it could happen--heck, in 1984, Joe, Jr. would be younger than the three leading candidates for the 2020 Democratic presidential nomination today (as well as the POTUS)!
I absolutely acknowledge that in OTL three Kennedys as president in the way some people dream ("if only RFK hadn't been killed in 1968, he'd go on to two terms and the be succeeded by Teddy in 1976") is very unlikely (though no more so than many things we have taken seriously here). But there are other ways three Kennedy brothers could become president as some time, if we just imagine a somewhat different world.
And you have forced me to reveal prematurely how different that world would be: To the question of why JFK was court-martialed, I was going to explain that President Wallace had a grudge against Joe, Jr.'s father...
