It is understandable that these leftists who were merely born Jewish, are trying to "shame" Jews who are not leftists. It's because their religion is leftism.
That's how they see the world. They merely have tribal/social/historical connections to Judaism.
It's quaintly obnoxious and pathetic that they use the word "shanda" which is probably the only Jewish concept that they know about except for bagels and lox.
Regardless, the thing that probably irriates them the most is that President Trump has a Jewish daughter, a Jewish son-in-law and Jewish grandchildren. In other words, he has a child who has a Jewish spouse and has made Jewish babies.
I bet most of his "Jewish" critics cannot make the same claim and this bothers them on a very primitive and wordless level.
So basically, they can all bite me.