This was pure spectacle. Anything eye-catching or theatrical drew people towards it, and caused the clicks of a hundred cameras. Everybody seemed to have cameras. The police filmed the protesters, the protesters filmed the police, and the media filmed the protesters and the police. But protesters with ideas tended to be even worse than these harmless exhibitionists.
Humans are shitter than pigeons.
Despite the feebleness of protesters, the 6000 police officers were determined to get and keep control, and they seemed confident that, unimpeded by the obstructions of civil rights, they could do exactly what they wanted. The awkward youths on Nelson's column were replaced by groups of yellow-jacketed policemen at each of the four corners. Public Order Act. Yes - it is illegal to have leaflets, if they decide it is. By most accounts, there were far more police than protesters.