In alluding to the Festival of Britain in 1951 you could have contrasted the current situation with the role played at that time by the London County Council. That authority was able to clear the South Bank, build an embankment wall, construct the Royal Festival Hall in time for the exhibition and make temporary improvements to the roads east and west of Westminster Bridge and to the south of Waterloo Bridge.
In addition, the LCC was granted special facilities to develop "Lansbury" in London's East End as an exhibition of "live" architecture with provision for schools, open spaces, shops as well as dwelling houses.
Regrettably, all the experience that went into the Festival of Britain was destroyed when the LCC's successor body, the Greater London Council, was abolished in 1986. Had it still been in existence, that council would have been the ready-made and ideal instrument to assume overall responsibility for the capital's contribution to the millennium celebration.