If you know the history of Israel, that the country was created after one-third of the world's Jewish population was murdered by Nazis (it has yet to fully recover), it's difficult to stomach protesters who often slip from supporting the Palestinian cause to gloating over Hamas's terrorism and the prospect of destroying the Jewish state. There's not a lot of good will in projecting "Glory to Our Martyrs" on buildings or chanting "from the river to the sea"—let alone explicit endorsements of the attack.
But even assholes have speech rights. That's because all individuals have rights, however they use them, and because free expression only works if it's available to everybody, not reserved as privilege for the "right" ideas. And, importantly, respecting free speech lets people show us who they are.
