TL;DR: New York had more antisemitic attacks than all the red states combined.
We additionally knew because I saw where Europe was going in 2014. Me in Time Magazine:
“Israeli performers get disinvited from a festival in Edinburgh as if disinviting artists from countries whose politics you don’t like is a normal thing to do. Where is the outrage? They pretend it’s because of Israel, not because they’re Jews. Then the Jewish Film Festival gets canceled in London. An embarrassment. Britain should hang its head in shame. It doesn’t. A crowd in Germany (in Germany!) shouts “Hamas, Hamas, Jews to the gas.” Where is Germany’s soul-searching that this goes on within its borders? Forget Penelope Cruz and Javier Bardem signing an anti-Israel letter in a Spanish newspaper. No big deal when the second-biggest newspaper in Spain prints a piece arguing Jews “are not made to co-exist,” with references to how good they are with money, how they deserved expulsion, wondering how they still exist (“persist”) at all.”
It’s impossible to dismiss any of this as just a province of the “left” at this point. No one thinks the next Democrat running for president will be a friend to Israel. No one expects the mayor of New York City, home to more Jews than Tel Aviv, is going to stop the violence in his city against Jews. No one waits for the mainstream Democratic establishment to say a word about pograms in Brooklyn or dog rape lies in the New York Times. They have picked their side and Jews are not on it. Liberal Jews can decide for themselves what that means for them personally.
But for the rest of us living in reality we need to understand the truth of the story of leftist violence that the ADL numbers tell and act accordingly. We have to monitor the podcastistan hate on the right but be realistic about the real life, actually violent, hate from the mainstream left. Conservative donors have to stop funding “the fight” against antisemitism, especially when groups stay blind to where that fight is happening. Put the money elsewhere. Raise strong Jewish children. Teach them to know who their friends are and to never pretend otherwise.