Abdeslam (the last terrorist from the france attacks) was arrested in Belgium 3 days ago and upon his removal from the area, youths gathered chanting his name and throwing bottles at the police combis. The national media chose not to cover this for the same reasons you laid out and it has caused a bit of a furore in Belgium.
The distinction between racism and the fight against bad ideas (religious extremism) is often blurred by both the extreme right and the left.