I think the point being made is that antisemitism has been around for thousands of years, and the groups you're talking about have been around for 100. So they don't explain anti-semitism.
Assuming that OP hasn't been around for thousands of years himself, I could only point out modern day antisemitism which makes perfect sense. OP never asked for a complete history.
However, if you're going to get to the root of things, you'd have to bring up religious prejudices passed down through the centuries as well as the origin of money lending and banking which undoubtedly cast Jews in a bad light.
Firstly, I don't agree that modern day antisemitism makes sense because of those groups.
But even if that were the case, you're making a pretty ridiculos argument:
1) Antisemitism has been around for a thousand years, before certain organizations existed.
2) Antisemitism is still around now.
3) Now it makes sense, because those organizations exist.
Whereas it makes a lot more sense that these organizations are an excuse for antisemitism, not the cause. After all, antisemitism has been around non-stop for thousands of years, there's no reason to think that it would have stopped had these organizations not existed.
The person you're responding to is saying that the zionist movement is a major reason for modern antisemitism. That antisemitism predates the zionist movement has no power to refute his point, unless the reasons for antisemitism have been static throughout history, which they haven't.
