Is anti-Zionism anti-semitism?
I think that is hard to answer because I do not think there is one clear definition of Zionism and the term seems to be used in many different ways and it seems to have many different meanings among Jews as well.
Haaretz has a good article on this:
Defining Zionism: The belief that Israel belongs to the entire Jewish people - Opinion
...If so, how would we define who is a Zionist, starting from the emergence of the Zionist movement as inspired by Theodor Herzl and his associates? Here is the definition: A Zionist is a person who desires or supports the establishment of a Jewish state in the Land of Israel, which in the future will become the state of the Jewish people. This is based on what Herzl said: “In Basel I founded the Jewish state.”
The key word in this definition is “state,” and its natural location is the Land of Israel because of the Jewish people’s historical link to it. Thus my grandfather’s grandfather, for example, who came to the Land of Israel from Thessaloniki in the mid-19th century, cannot be considered a Zionist. He came to settle in the Land of Israel, not to establish a state here. This is also the rule for the ancestors of Neturei Karta and other Hasidic groups that came to the Land of Israel as far back as the 17th and 18th centuries, and who remain loyal to it. Not only were these Jews not interested in establishing a Jewish state, but they include some who saw − and still see − the State of Israel as an abomination and a desecration of God’s name.
A Zionist, therefore, is a Jew who supported the establishment of a Jewish state in the Land of Israel, and not necessarily one who actually settled in the land. Herzl himself and many Zionist leaders never settled in the land, yet you wouldn’t hesitate to call them Zionists. Even today, the members of Zionist federations worldwide are considered Zionists by us and by themselves, even though they don’t live in Israel.
...Ever since the State of Israel was founded in 1948, the definition of “Zionist” has been revised, since we don’t need to establish another state. Therefore, its definition is as follows: A Zionist is a person who accepts the principle that the State of Israel doesn’t belong solely to its citizens, but to the entire Jewish people. The practical expression of this commitment is the Law of Return.
Interesting take on it, because it also points out that a lot of the issues and struggles Israel deals with really have nothing to do with Zionism but are issues facing many other countries as well.
Here is another question though - does Zionism affect territorial aquisition? Is the desire to settle the Occupied Territories with Jews an expression of Zionism as a desire to regain all of what was once the ancient Kingdom of Israel and is criticizing that anti-semitism? I would say no.
I always associated "Zionism" with "Manifest Destiny" - a concept that there was a right, given by God, to a territory.