You could try highlighting:

• Jewish opposition to Zionism
• How the overwhelming majority of our Senators, Representatives, Governors, Supreme Court Justices, etc. are not Jewish. There has never been a Jewish President or Vice President of the United States in the entire country’s history.
• Instances throughout history in which the U.S. government has successfully used its leverage over Israel in order to force them to pursue a certain course of action (e.g. the withdrawal from the Sinai Peninsula in 1957, the decision not to destroy the encircled Egyptian 3rd Army during the Yom Kippur War, and Reagan forcing Israel to end the bombing of Beirut in 1982). This demonstrates that it is in fact Israel which is (to at least some extent) controlled by the United States and not the other way around
• The long history of collaboration between Zionists and anti-Semites; how both ideologies are supported by the same people and serve the same financial interests
• How Zionism does not exist in isolation but rather is part of a broader phenomenon of European settler colonialism

If that doesn’t work, no amount of reasoning will. Unfortunately, you can’t logic someone out of a position they didn’t logic themselves into. They have to be willing to learn. Not that that means you should just abandon them, but as you said, the solution will have to hinge on an emotional approach

it’s trans men, not “transmen”; and trans women, not “transwomen”. Trans is an adjective, meaning it’s a word that describes a noun. A trans man is a man who happens to be trans. The (grammatically incorrect) usage of trans as a noun (“a trans”, “transman”, “transwoman”, “transperson”, etc.) is a dogwhistle meant to imply that trans men aren’t men and trans women aren’t women but some separate category