Perhaps I was unclear, but as far as your word-salad accusation, I certainly don't hold Jewish people in general, or even Jewish people in Israel, responsible for everything, or even anything in particular, the government of Israel does. Like any democratic country, citizens at some level have influence on the state, but that doesn't hold for individuals. And as far as I am concerned that is nothing to do with their Jewishness as such, although they themselves may see them as connected.
As for who is pushing the idea I suggested - plenty of individuals, they show up on MN all the time, but also some Jewish organizations. "Official" definitions of antisemitism often get trotted out which essentially say, any qualms about Israel, politically, are a form of antisemitism.
I am not talking so much about specific actions the government takes, though that can come into it. But lack of support for Israel as an ideological construct is clearly seen as antisemitic.
My point is that whether or not anyone in this thread agrees or disagrees with that, as a definition of antisemitism it clearly links political support for a particular nation-state with the Jewish people as a whole. And yes, actually I am aware that there are and always have been plenty of individual Jewish people who don't agree with that, and who are even not supporters of Israel ideologically, but that's neither here nor there as far as the effect this kind of rhetoric has had on how people think.