To put it simply: Joe Kennedy recently announced in a debate that he does not consider Jerusalem to be the capital of Israel.
This is not only a rejection of the commonplace observation that "every country has the right to designate its own capital"; it's also a rejection of Joe Kennedy's own public and official opinion on the topic.
You'll notice that I quoted that statement above. That's because I happened to have agreed (on that, at least) with whoever Joe Kennedy's family hired to do his Israel policy thinking for him. A shame that that guy couldn't have done the debate, but I guess that there's a limit to how much you can delegate work.
Moe Lane (crosspost)
PS: The video above was released by Sean Bielat, who is one of the candidates for the Republican nomination in MA-04. The primary is this Thursday.