I've been generally supportive of Israel's actions, but I can also openly state that there is a wing of the Israeli government that has no real desire for actual peace and that needs to be thoroughly excised once the war is over if there's to be any hope of making some progress towards peace.
That said, reading the article, this seems like an asshole attempting to make a crude joke more than an actual legal threat. What he actually said wasn't "If you protest the war, I will forcibly send you to Gaza", it was "If you like Gaza so much, I'll gladly help you get there by offering a bus".