That gap between support of Israel across age groups existed historically AFAIK, although the margins were narrower.
More worrying for Israel is that it's becoming a partisan issue. That goes to both ends - previously unthinkable, unwavering support under Republicans but a very short leash under the Democrats.
> More worrying for Israel is that it's becoming a partisan issue.
A highly salient political issue becoming partisan is a good thing in a representative democracy, as that is the only thing that makes it possible for the public to influence it by general election votes.
In FPTP, this often ends up backfiring. A politicized issue quickly becomes a polarized issue - the other side takes the opposite view, and both sides then race to the extremes. Compromise becomes less and less possible, because then each side sees it as a defeat. Nothing ends up done.
Every possible alignment of circumstances “backfires” in FPTP because FPTP is a fundamentally bad way to elect a legislature.
That’s not a problem of, e.g., salient political issues becoming partisan—representing a coherent position on salient issues is the only useful thing parties can do—it is a problem of FPTP.
Worse there is always more than one issue. Now I can't even find someone in my own party to support as the race has brought them all the same way on this. And so I either support one of them anyway for other issues or I leave.
More worrying for Israel is that it's becoming a partisan issue. That goes to both ends - previously unthinkable, unwavering support under Republicans but a very short leash under the Democrats.