it’s not like AIPAC is super popular with American Jews either.

It’s been super popular with Zionist American Jews. It’s also popular with the vastly larger number of non-Jewish Zionists. Quite a bit of this is coming from Christian conservatives. AIPAC Not Just for Jews Anymore

any country could basically do it.

Not really: the US would shut it down if it ran up against US interests enough. But Israel doesn’t run up against US interests; it’s in line with them. Israel is the US’ unsinkable aircraft carrier in West Asia. As Biden has said throughout his career, “Were there not an Israel, the United States of America would have to invent an Israel to protect her interests in the region.” A lot of this money and influence is coming from the US military-industrial complex.

Israel isn’t a case of the tail wagging the dog. It’s a symbiotic relationship.