This is the worst thing any US president has ever done to Israel:
"Trump: unfair for Iran to lack ballistic missiles if other countries have them":
https://www.reuters.com/world/middle-east/trump-unfair-iran-lack-ballistic-missiles-if-other-countries-have-them-2026-06-17/(Remember that ~45% of Americans believe every single thing Trump says and trust his decisions implicitly, and will formulate their ideas about Israel exclusively based on what Trump tells them--so the damage this statement did is simply incalculable).
Trump turned Israel into a partisan football: "Democrats hate Israel", he said. Only he and his party would defend them, he said. In other words, he stamped the word, "Republican" on Israel in the US culture wars.
Now he's seen that he was duped by Netanyahu into starting a war with Iran, and he wants to pull out of that war before it gives Americans the minor inconveniences that wars often do, thus diminishing his popularity for the upcoming elections. To Trump, Israel is totally meaningless: the only thing that is meaningful is his own political status.
Before the war, supporting Israel was popular among his base and himself. Now it's unpopular.
In conclusion, Trump took bipartisan support of Israel and intentionally divided it for political purposes, placing himself solely in charge of whether American support Israel. Then the minute Israel became politically inconvenient, he reversed himself on them. Vance recently threatened to cut off their aid entirely, which is something most Americans want now.
Because of Trump, Israel has no serious constituency in the USA--and the rest of the world hates them too.
So I agree with the OP: no president has done more for Israel than Trump--if you mean more BAD things...