A few days after Hamas’s ruthless slaughter in Israel last October, I found myself watching videos on social media of crowds in the streets of Amman, Jordan celebrating the attacks. The commentators posting them expressed a mixture of outrage, bafflement, and indignation at the videos. As someone who has lived in Jordan and has a deep love for the Jordanian people, I believe the scenes serve as an important cautionary tale that we would be wise to pay attention to here at home—especially as we grapple with pro-Hamas demonstrations and rising antisemitic behavior within our own borders...