Probably the thing to figure out is how that surface-level understanding is even formed.

I think probably the biggest factor is simply the fact that WW2 occupies such a large space in the American historical zeitgeist. WW2 is a story that makes us look good, and we like stories that make us look good, so we keep telling them. And in the WW2 story, the jews are the victims, and their happy ending is creating a homeland of their own. So the American view, by default, is that Israel has an ethical right to exist as a home state for the jewish people.

Many jews in the united states, especially older jews, are very sympathetic to this view. While they have never experienced systemic persecution themselves, the jewish community at large is bonded over their historic persecution and internally reinforces these norms. Meanwhile, jewish people are significantly overrepresented in the entertainment industry, in wealth, and in positions of political power. The meme of “jews run the world” is a conspiracy theory - but jews do have an outsized influence in society relative to their population. This is likely due to founders effects of immigrating with some level of wealth or expectation of wealth, compounded over time with the additional benefits of being part of a social network which advances its own. For example, a young jewish comedian will have another jewish comedian friend who has an aunt who has a friend who knows Seinfeld’s neice’s boyfriend, who can arrange for him to open at a moderately popular LA comedy club. Being part of the jewish diaspora will give you opportinities that you otherwise wouldn’t get. And so you have a lot of wealthy jews in positions of power in the government and the media, with a culturally imposed mandate to consistently remind the non-jews of the jewish history of persecution and the need to support and protect them from further persecution.