It all depends on how one DEFINES Zionism.
If one equates Zionism with the radical, totally secular, anti-Torah movements of the Israeli left wing, then certainly Torah Jews should oppose THAT.
However…
If one equates Zionism (as I myself do) with the national,’geographical’, i.e. Eretz Yisrael component of Judaism, which is a very central and integral part of what Yiddishkeit IS, then every Torah Jew, by definition MUST be a Zionist.
You don’t think so? Did you skip last week’s parsha?
Why did HaSh-m tell Avraham Avinu to go to Eretz Yisrael? THAT is Torah Zionism.
Why did HaSh-m take the Jews from Egypt to Eretz Yisrael, and not just free them in Egypt and give them the Torah to study and observe THERE? THAT is Torah Zionism.
Do you say (at least at the end of your seder and at the end of Neilah) “L’shanah Ha’ba B’Yerushalayim” – WHY? THAT is Torah Zionism.
Do you daven EVERY day “l’Yerushalayim Ir’cha, b’rachamim tashuv”? THAT is Torah Zionism.
Do you think that the Neturei Karta pals in Teheran would be hugging them if they knew that those guys say that 3 times a day?!?
Certainly JUST being in Eretz Yisrael without Torah study and observance is NOT what being a Jew is about. But just as certainly, being observant WITHOUT, at the very least, aspiring to live in Eretz Yisrael is also NOT what being a Jew is about.
We don’t cast aside the title of being ‘human beings’ because there are all sorts of horrible people that share that title. Let us not cast off the title of ‘Zionist’ because there are anti-Torah frei Yidden that share THAT title.