Free Movement Of People?

Picking up on a blog by Daniel Hannan, it would seem that one of the 'freedoms' of which the European Union is so proud ain't such a freedom as might have been first thought.

This Dutch politician first came to my notice in a post by Cranmer, who highlighted the fact that a Muslim peer threatened to have 10,000 Muslim protesters on the streets if Geert Wilders screened his controversial film.

Apparently the reason given for barring Geert Wilders is his visit would constitute a threat to pubic order.

Is not the threat of having 10,000 Muslim protesters on the streets a 'threat to public order'?