The boundaries of free speech in Europe widened Thursday after a Dutch court acquitted politician Geert Wilders of inciting hatred against Muslims when he compared Islam with Naziism and called for a ban on the Quran.

Political analysts say the ruling will likely embolden Wilders and other right-wing populists across the continent to ramp up their anti-immigrant rhetoric, with remarks like Wilders' call for a "head rag tax" now squarely within the boundaries of fair political debate.

The ruling did lay down a clear limit: Calls for violence remain out of bounds. Wilders, who has lived under constant police protection due to death threats since 2004, has never called for violence or endorsed it.

Presiding Judge Marcel van Oosten said some of Wilders' comments — such as saying foreign influences are "breeding" in the Netherlands and threatening to overrun Dutch culture — may be "crude and denigrating." But he said they did not amount to inciting hatred and must be seen in a wider context of a fierce national debate over immigration policy and multiculturalism.

While the United States has enshrined the right to freedom of speech in its Constitution, many European nations introduced hate-speech laws in the wake of World War II, determined to prevent the scapegoating of minorities.