Being anti Zionist is being against Jews having a state in their historic home. Seeing as every other religious group have states in their historic homes, I'd call that anti Semitic[.]Sometimes the claim is less specific, declaring that Jews have a right to a state of their own (as "every other religious group" allegedly has), without necessarily laying claim to a specific stretch of territory in the Middle East. But in whatever form, it makes no sense to me.
What, for example, would be "the historic home" of Christianity? The Jesus cult originated in Judea and Galilee; wouldn't this mean that Christians have a right to a state in their historic home? Buddhism originated in northern India but, like Christianity, spread around the world. For that matter, Judaism also spread around the world, though in much smaller numbers because Judaism is not a missionary religion. Europe is the historic home of a variety of non-Yahwist religions. So are the Americas. Which of those religions can and does have a state in some piece of turf?
For that matter, what is the historic home of, say, Methodism? It originated in England, yet Methodists don't have a state of their own. Except for Catholics, who have Vatican City, no Christian sect does. Some countries have official state religions, but I hope no one would claim that Germany, for example, as the historic home of Lutheranism, is entitled to treat all non-Lutherans as second-class citizens. When racists try to block immigration, they are usually at least as concerned about language and "culture" as they are about religion. And despite those who want the USA to be a Christian nation, this country has no official religion, but does have an official policy of religious toleration and pluralism.
The argument that Jews have a right to their own state, wherever it's located, seems to agree that a state properly will consist of one "race," one "people," one language, one religion. It would then follow that discrimination against minority races, peoples, languages, religions is legitimate, and Zionists simply want a state where they can push others around. Perhaps they are entitled to such a state, but it would also follow that complaints about discrimination, marginalization, even persecution of minorities are invalid. Anti-semitism in Europe, the Middle East outside of Israel, or anywhere else, is on this Zionist argument perfectly legitimate, as is racism generally: it's merely the natural outcome of a state defined as a "homeland" for religion and ethnicity, and if you're not comfortable where you are, you should go back where you came from, or where your distant ancestors came from. If there other people living there, you can just kick them out and take back your historic home.
It's true that Judaism is a bit of a holdover from the days when religion was usually associated with place and culture. The Greeks had their gods, the Romans had theirs, the Babylonians and Assyrians and Egyptians had theirs, and Israel had its gods. (It took a long time for Israel to purge all of Yahweh's competitors.) All of these states had permeable boundaries, however: some of their natives traveled for trade or whatever reason, taking their gods with them, and natives of other nations brought their gods with them when they came to trade. This was true of Israelite religion too: there was a diaspora even before it was accelerated by various national disasters: the conquest by Babylon, the conquest by Rome. Buddhism, and later Christianity and Islam broke with this model, detaching religion from native land -- and also to a great extent from family.
So India is the "historic home" of Buddhism as well as Hinduism and Jainism; but India also has a large Muslim population. China is the "historic home" of Confucianism and Taoism, but it also provided fertile soil for Buddhism. Should these interlopers (and sometimes invaders) be kicked out so that India and China can be the states of their respective religions? This would mean that all Buddhists in East Asia would either have to relocate to India, abandon their religion for the supposedly native religion where they live, or accept a status of religious aliens there? This would solve the problem of Tibetan Buddhism, which would simply have to give up any claims to that country. I don't think many people anywhere would want to follow this logic to its conclusion. Linking religion to place and ethnicity is one of the defining symptoms of racism, nativism, and religious bigotry.