The present kerfuffle about flying the Union flag over Belfast City Hall is a reminder of how long it takes to change anything and of the obstacles in the way of change. It used to be that the Union flag was flown 365 days a year from anything vertical a unionist could find - at police barracks, courts, council offices, libraries, hospitals, education offices,schools and, more surprisingly, Protestant churches, never mind unofficial efforts on lamp-posts and pylons.