1. The OP did *not* mention Israel or Palestine, it was you who introduced them into the conversation.
2. You claim that ‘the tragedies of WW2 [are] the first thing people think about’ regarding Israel. Said tragedies had nothing to do with the State of Israel, which did not exist at the time, they were specifically about Jews living in Europe, and the extermination thereof. And again, you are the one linking this to Israel, which was not part of the conversation until you brought it up.
3. You very much did not, you said, ‘I'm sorry for everyone who's treated badly due to their background, and not due to their ideas.’, which, given the current state of discourse and the tendency to identify non-Israeli Jews with Israel and Zionism, is precisely one of the ways in which antisemitism is excused through the assumption/insistence that all Jews must believe certain unacceptable things vis a vis Israel and Palestine.