It's considered very anti-semitic in America to be against male genital mutilation.
https://en.wikipedia.org/wiki/Anti-Defamation_League#Circumc...
When Iceland tried to ban it, the ADL had some very choice words about the potential consequences.
> Greenblatt sent Iceland's Parliament a letter regarding a proposed infant circumcision ban in that country, arguing that the ban should be rejected due to circumcision's religious significance and health benefits. Greenblatt also said that if the ban passed, the ADL would report on any celebration by antisemites and other extremists, asserting that this would deter tourism and harm Iceland's economy
It's scary stuff.
That isn't even the point though. The circumcision itself is perfectly legal in Belgium. The legal issue is with the lack of qualifications of the ones performing them in this case.
The ADL is a rather discredited pro-Israel organization. It reports protests of Israel and of Zionism as "anti-semitism". Here's a link to a documentary about it from 2009:
> the ADL would report on any celebration by antisemites and other extremists, asserting that this would deter tourism and harm Iceland's economy
If everything is antisemitism then nothing is antisemitism.