I think it's odd to suggest that the Israel-Palestine conflict is perpetuated by Islamism when Israel's own existence hinges on a moral absolute.

There is a small but influential undercurrent among Israeli Zionists who believe in the creation of Greater Israel, ethnically cleansing not only all of the current borders of Israel (including Gaza and the West Bank) but also historical Transjordan and territories all the way to the Nile (i.e. all of Jordan as well as parts of Syria, Saudia Arabia and Egypt): https://www.newyorker.com/news/q-and-a/the-extreme-ambitions...

Eliminationist rhetoric has repeatedly made its way into statements by government politicians and even programming by the Israeli national broadcaster (Kan) as in the recently broadcasted and immediately de-archived "friendship song" video: https://www.msn.com/en-my/news/national/music-video-of-israe...

The early Zionist project in Palestine was explicitly described as colonialist by key members and the expulsion of the non-Jewish Palestinian population as an explicit aspect of it. The support of Western governments including the UK pre-1945 was based more on antisemitism than genuine goodwill, ranging from the idea that having "all the Jews in one place" made them easier to handle (or eliminate - which was why the Nazi government tolerated Zionist transfers of German Jews to Palestine until WW2 shut down all emigration) to the British idea during WW2 that "giving them what they want" would give you an "in" with "the international bankers" (basically the reverse side of the Jewish conspiracy theories): https://www.haaretz.com/opinion/2017-10-26/ty-article/the-ba...

It's also impossible to mention the Israel-Palestine conflict itself without mentioning how Israel effectively helped bolster (Islamist) Hamas in order to combat the (secular, socialist-leaning) Fatah: https://www.washingtonpost.com/news/worldviews/wp/2014/07/30...

... or how current PM Netanyahu supported the calls for the murder of his more moderate predecessor Rabin that preceded his assassination: https://www.timesofisrael.com/labor-chief-michaeli-rabin-was...

Heck, if you go back to the time Hamas was actually elected in Gaza (and many Gazans alive today weren't alive at the time, let alone old enough to participate in the election), their messaging was a lot more ideologically (and religously) moderate and closer to that of Fatah, even if they already were Islamists and eliminationist antisemites internally. Note that Palestinians in Gaza haven't had another election since and public opinion among Gazans seems to be very much divided.

In effect, the Zionists through the creation of Israel and the domestic and military conflicts that sprang from it created a Palestinian diaspora (https://en.wikipedia.org/wiki/Palestinian_right_of_return) which is being mistreated in the countries it has sought refuge in. At the same time, Israel's existence in explicit opposition to its neighbors' cultures and ethnicities while in close alliance with Western powers and the US in particular is seen as a geopolitical threat by its neighbors and especially those countries that are aligned opposite to the US - this more than any religious motivations seems the main motivation behind Iran's support of Hamas in Gaza and Hezbollah in Lebanon.

Islamism definitely plays a part in this and Islamists do lend themselves more towards carrying out the terrorist attacks and missile strikes against Israel as none of its neighbors could risk an all-out war even without direct involvement of the US military. But as always in geopolitics it runs much deeper than one group's religious dogma.

And I haven't even mentioned how certain Evangelical Christians shaped US politics on Israel because the reestablishment of Israel as a "Jewish state" (and the extermination of those same Jews) is an integral part of their mythology of the "end times" (and salvation). There are very unhealthy beliefs about Israel/Palestine present in all three Abrahamic religions, to say the least.