BS”D
Zionism is not diiferent than any other “Ism” (Communism, Evolutionism, Capitalism, Charadism, MOism, etc.) that takes one away from the goal of Avodas Hashem and Kiddush Shem Shomayim. It is when the system becomes more important than the results.
The issue with the Medina is “Having a Medina at all costs”, which is Zionism. One has to remember that the goal is not the system.
That all being said, Avi K., M in Israel, & HaKatan are all correct. The Gedolim before the war were (mostly) against Zionism as the system took away from Avodas Hashem and made “The State of Israel” into the goal. That does not mean they were not “Loving EY” and settling the land, but they did not make it the end all.
That also has nothing to do with the current Satmer Shitta, that “the state” is Assur. One can be part of the state while not fully suscribing to “the system” (as most Israelis do at this time as well).