AMSTERDAM — Surely, you could think, the Oslo mass murders might well bring some moderation to Europe’s far-right populist parties in their unyielding denigration of Islam and their Armageddon-is-nigh vision of a future shared with Muslim immigrants.

At the same time, since Norway’s massacre led to statements by populist leaders rejecting violence, you might also suppose that the European left could ease up on its resistance to the idea that multiculturalism has brought parallel societies, disrespect for national laws and traditions, and a threatened sense of identity to countries with hundreds of years of democratic history.

Neither assumption is hopeless. But each enters the area of very wishful, perhaps naïve surmise.

If you take the Netherlands (including Geert Wilders, the Dutch Freedom Party chief who is Europe’s most abrasive anti-Islam voice) as a prime arena for Europe’s kulturkampf concerning Islam’s place in its midst, Norway’s tragedy has not narrowed its divisions.

The Dutch have reason to think they have been a kind of pace car in the issue’s development over the last decade.