Queen Elizabeth II: The power of the 'royal silence'

As the UK celebrates Queen Elizabeth II's 70 years on the throne, her style of monarchy has been the focus of much discussion. Author Tina Brown says the Queen's "remarkable combination of temperament, judgement and composure" has meant people are unsure what she is thinking, and that this has been a "unifying power".

Photo: Queen Elizabeth II watches a show in the village of New Karu near Abuja, 04 December 2003 (Credit: Getty Images)