There are probably a lot of reasons I haven't encountered.
Among the common ones I have are things like Palestine being like a lawless laboratory where industrialists are trying out new gadgets and systems on human populations, which is an important driver in civil as well as military state power towards both their own populations and foreign.
It's also one of the last surviving colonial projects and some old money dynasties stick by it for nostalgic or geopolitical reasons. Related to this is a common form of racism, where the state of Israel is perceived as a civilised western bulwark against the unshaven barbaric hordes of the east.
Then there are religious convictions, especially common among usians, who are often of the belief that there is a God that has a plan for the cosmos that involves first telling the jews about ethics and then replacing them with christians but keeping the jews around as the first line of defense in the ultimate war to end all wars and history itself. Usually this is expressed as a philosemitic form of antisemitism where they see themselves as kind of stewards of the jewish diaspora communities and take on themselves the purpose of moving all jews close to Jerusalem, where this final war is supposed to begin. It's not uncommon that these people perceive arab and persian muslims as basically an Antichrist entity that needs to be eradicated, either in the short term if they're uppity or kept in some form of economic or political bondage.
While there's a lot of conspiracist beliefs surrounding it I'm also convinced there is some truth to the view that israeli security services keeps a lot of kompromat and similar tools of power involving rich and powerful people. Open assassinations and the like have backfired sometimes, e.g. the Lillehammer scandal, and I suspect that this has pushed israeli security to try to adapt to more shadowy tactics.
And then you have people with Holocaust or related forms of shallowly antiracist anxieties, that have convinced themselves that the jews deserve Palestine due to historic attempts at extermination. This is somewhat related to christian zionist beliefs where jews are considered somehow special, 'a chosen people', which is why they are supposedly deserving of an atrocity-laden settler colonial project but e.g. the cirkassians are not and they don't care about the christians of Artsakh and so on.
Plus the economic opportunities due to huge free-money investments into corporations situated in Israel and more mundane imperial considerations like the geopolitical positioning as a destabilising force between Eurasia and Africa as well as on the edge of Eurasia itself. The Mediterranean is small but imagine if there was high-speed rail and a decent degree of social and economic integration all the way from South Africa and Mauritania up to Europe, that would make this a hugely important economic and political area and North America would look puny and useless beside it, due to being surrounded by oceans and so on. Israel also happens to be a base for nuclear weapons placed really close to some of the largest energy reserves on the planet, and largely dependent on states really far away that in turn are highly dependent on the exploitation of these energy reserves.
Also, some people are plain sadists. They feel pleasure and giddiness when they know there are other people on what they perceive as their team doing the worst of things, just the nastiest possible stuff, the most excruciating forms of hierarchy and power imbalance. Sometimes because that makes the power imbalances that keep them in place look relatively sane and tolerable.