Criticizing specific Israeli policies is certainly not intrinsically anti-Semitic.
Indeed, many Israelis are critical of some of their nation's policies. But support for Hamas is anti-Semitic, because Hamas's policies and actions are based, at their core, on Jew-hatred.
Yet many prominent individuals, some out of ignorance, many more with full knowledge of what they are doing, are overtly supporting Hamas. Some have even praised it. Others, like Italy's most famous philosopher, Gianni Vattimo, are trying to raise money and provide material support to this anti-Semitic terrorist organization. Still others refuse to condemn it, while condemning Israel in the strongest terms.
Here is part of what the Hamas Charter, which continues to articulate its governing principles, says about Jews: "The enemies have been scheming for a long time. [Their] wealth [permitted them to] take over control of the world media such as news agencies, the press, publication houses, broadcasting and the like. [They also used this] wealth to stir revolutions in various parts of the globe... They stood behind the French and the Communist Revolutions... They also used the money to establish clandestine organizations which are spreading around the world, in order to destroy societies and carry out Zionist interests. Such organizations are: the Freemasons, Rotary Clubs, Lions Clubs, B'nai B'rith and the like. All of them are destructive spying organizations... [T]hey stood behind World War I, so as to wipe out the Islamic Caliphate... They obtained the Balfour Declaration and established the League of Nations in order to rule the world by means of that organization. They also stood behind World War II.... They inspired the establishment of the United Nations and the Security Council to replace the League of Nations, in order to rule the world by their intermediary. There was no war that broke out anywhere without their fingerprints on it."
Most of these allusions to "the enemies" pertain to events that precede the establishment of Israel. The charter plainly means "the Jews," and it invokes the usual tropes of anti-Semitism and Jew-hatred.
It expressly calls for the murder of Jews, citing Islamic sources for its genocidal goal.
Hamas has been looking forward to implementing Allah's promise, no matter how long it might take. "The prophet, prayer and peace be upon him, said: The time will not come until Muslims will fight the Jews; until the Jews hide behind rocks and trees, which will cry: O Muslim! there is a Jew hiding behind me, come on and kill him!" This should not be surprising. Hamas is a wholly owned subsidiary of the Muslim Brotherhood, which is an outgrowth of the German Nazi Party. The brotherhood was founded in 1928 by Hassan al-Banna, a close ally of Adolf Hitler. It worked hand in hand with Hitler during World War II, establishing the Muslim Waffen-SS Handschar Division, which committed war crimes against Jewish communities. It then helped to rescue Nazi war criminals following the defeat of Nazism and the disclosure of the Holocaust.
Nor is the charter and origin of Hamas merely past history. Current Hamas leaders frequently invoke the blood libel, accusing "the Jews" of killing Christian children and using their blood for the baking of matza. They regard Jewish places of worship and Jewish schools, anywhere in the world, as appropriate targets for their terrorist attacks.