As mentioned, I recommend going directly to the source. The clearest indication of what Zionism is the father of modern Zionism and Israel: https://www.gutenberg.org/files/25282/25282-h/25282-h.htm

It's a hundred pages. If someone hasn't read it, or even a summary, they have little knowledge of Zionism. WW2 was far after the modern return of Jews to Israel.

I grew up in a very left leaning, pro terrorism household. I was absolutely wrong about what Zionism was - not a 'God promised me this because I'm special" as I was told but rather "racism means we need a homeland let's all go back to Israel".