Anti-Zionism is an ideology that is opposite of Zionism. It says that the Jewish people do not have a right to establish a state in their original homeland. Many go on to say that Jews are occupiers and should be removed or destroyed.
There are lots of Jewish anti-Zionism. The anti-Zionist ultra-orthodox Jews meet and praise anti-Semites and the Holocaust deniers. They say the Holocaust was exaggerated which gives support to anti-Semites. Some Jews were afraid that the state of Israel would hinder their acceptance as equals in Europe.
There is also Arab anti-Zionism. Nearly all Arabs and Arab Palestinians oppose Zionism, which they see as colonialism and racism. The Arabs and Palestinian Arabs believe the entire Middle East belongs to them, that Israel has no right to the land. Therefore, they oppose the existence of a Jewish national home and the state of Israel. Most of the Arab Christian believe in Christian Palestinianism, which say that Jesus was a Palestinian living in Palestine and therefore the Jews have no right to the land. They also believe in Replacement Theology - that the church has replaced Israel.
The anti-Zionist Marxists say that the Jews are engaged in colonialism and they denounce Zionist as being racists, believing that all colonialism is racism.
There is a large anti-Zionist group made up of Arab Christians, Messianic Jews, and evangelicals. It is called "Christ at the Checkpoint" or CatC. This group claims to be pro-peace but all representatives blame Palestinian suffering on Israel. They blame Israel for undermining the redemptive work of Christ and use replacement theology to prove their erroneous message.
Moslems are anti-Zionists by their own religious rules. They claim that Palestine was a land that was once ruled by Muslims and therefore regards it their duty as Moslems to not only retake the land, but to kill all Jews and all who will not accept Islam as their religion. Once land is taken by Muslims they say it belongs to them eternally.
Replacement Theology and Supersessionism are also anti-Zionists. They claim that God is through with the Jews because they rejected God's Son, Jesus Christ. Because God is through with the Jews, God has now replaced Israel with the church. They have done away with God's promise to the Jews of a return and restoration to their Land. Therefore, the Jews have no right to the land in Palestine and are occupiers of Palestine. One has to avoid the plain sense reading of God's Word to get such a meaning. For one place, in the Abrahamic Covenant, God promised the land to Israel for eternity. Replacement Theology and Supersessionists claim God will not fulfill this Covenant because the Jews rejected Jesus. If God changed His mind on this Covenant then there is no assurance that He will fulfill any covenant He made or any promises He made. However, God did not change His mind, He would cease to be God if He did..