I believe the terms of student visas could technically prohibit protesting for things unrelated to your field of study, if a judge decided to interpret it that way.
Except violating the conditions of your visa would be a crime, no matter how free your speech is. And the First Amendment is about criticizing the US Government, not Israel.
The first amendment is about freedom of speech, not about criticising either the US or Israeli government. I don't believe that one can agree to waiver their constitutional rights so I'm not sure those visa conditions would be legal.
> Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition *the Government* for a redress of grievances.
> Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging *the freedom of speech, or of the press;* or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
