Lured by local mosques and the Internet, by visions of warriors and victory dancing in their heads, thousands of European Muslims have left the safety of their homes in England, France, Germany, the Netherlands and elsewhere to join the Syrian jihad. Concern about the security threat they may pose on their return has gripped European leaders for some time; now, they are starting to focus on ways of stopping Muslim would-be jihadists from traveling to Syria at all.

But not everyone seems to think it's such a good idea: Pieter Broertjes, mayor of the Dutch city of Hilversum, for instance, thinks they should be allowed to go. "They're adults," he said in a radio interview Thursday. "Dutch went to Israel after World War II to fight the British, and we didn't try to stop them." (The reference is to the Palestinian territories, which was under British rule until 1948.)

Let's get this straight. Muslims who seek to join terrorist groups, killing innocent men, women and children in some of the most gruesome, inhuman acts of violence imaginable, are just like the Jews who escaped Europe after World War II?

What makes Broertjes' statement particularly shocking is that it comes just two months after a remark by another member of his party, the PvdA, or Labor Party, described IS on Twitter as a "Zionist plot."

The issue in the Broertjes interview was the proposal, raised in numerous European countries, to confiscate (or annul) the passports of anyone suspected of planning to travel to Syria – a suggestion Broertjes finds excessive. Earlier this year, a known Dutch Muslim radical, then living in Hilversum, left for Syria with his wife and children, escaping the notice of local officials – including the mayor's office.

Broertjes remark led to an online uproar, with Esther Voet, the director of the country's largest Jewish rights organization, CIDI, offering on Twitter to give him history lessons. In response, someone calling himself TweetBassam snapped, "Pieter was right, #ISIS and zionists are both terrorists, f***you cidi and you cu*t, Esther."

Broertjes has not responded to any of the criticism. Instead, a PvdA spokesperson apologized on his behalf, calling the remark "un-thought-out" and "unfortunate."

He has not offered to resign.