What do mean by "Usually"?  I'd say that judges in criminal cases get a good share of threats.

I do not "defend the criminality of threatening a sitting judge.".  However, I do not believe that "Trump bears some responsibility for threats like this".  Trump is trying to do what many people in the U.S. wants.  Many Europeans also would like a stop to allowing immigrants and refugees into their countries after they have suffered numerous attacks within their countries.