"Israeli-American dual citizens"

Making a big deal out of Israelis—especially wealthy ones—having dual citizenship is a classic antisemitic tactic, used to sow the idea that they aren't "real Americans" or their primary loyalty is to another country.

Also: yes, Citizens United is a big problem. But phrasing your comment as if the primary problem with it is "Israeli-American dual citizens" pouring millions of dollars into politics is perpetuating the antisemitic ideas that a) all or most Jews are wealthy, and b) Jews are controlling our country/the world.

Whether or not you meant it as antisemitic, it played directly and very clearly into multiple antisemitic tropes that are frequently used to try to smear and harm Jewish people.