I think the student who wrote the message should have every right to express her views, including views that support the killing of civilians. I most certainly don’t share the student’s views, and I do share the distinction that modern norms generally draw between directly targeting civilians (which is what Hamas has apparently done) and targeting military targets even when some civilians are inevitably killed. I also think we shouldn’t forget that the Hamas Charter is expressly committed to “struggle against the Jews” and the destruction of Israel (rather than just a shifting of the borders), and stresses a passage from the Quran stating,
The Day of Judgement will not come about until Moslems fight the Jews (killing the Jews), when the Jew will hide behind stones and trees. The stones and trees will say O Moslems, O Abdulla, there is a Jew behind me, come and kill him.
(See “When Hamas Tells You Who They Are, Believe Them,” by Bruce Hoffman, in The Atlantic.) This is a war to slaughter Jews because they are Jews.
But who is in the right and who is in the wrong in any war, and when it’s proper to kill civilians (Jews or Palestinians or otherwise) during a military attack, like any other such questions, are something that Americans must be free to discuss. Such positions don’t fall within any of the narrow exceptions to First Amendment protection. And while NYU isn’t bound by the First Amendment, it promises to protect academic freedom and free expression by their students.
This having been said, the student didn’t express the views herself in her own publication. She expressed them as the SBA President, in an SBA newsletter. I don’t think that student government officials have any right to use their offices to convey their own personal, controversial views that I expect many of their constituents and fellow officeholders don’t share. And it certainly seems to me quite proper for students to remove a President who does this, which the NYU SBA Constitution authorizes.