Monarchy may owe its survival in Britain to the fact the country was on the winning side in the wars, but the new Queen faced fresh challenges in peace.
Post-war generations were better educated than any before them. Social equality and advancement by merit became the prevailing principles of law and government, leaving an institution based on privilege looking outdated.
The institution survived by recasting itself very effectively as a family. The royal family turned the privilege of birth to an advantage, giving the public not just a constitutional figurehead but a real family unit to follow.
The arrival of its babies, their childhoods, schools, holidays, travels, relationships, engagements and weddings were staple items of interest. The royal family became celebrities throughout the world.
The family image brought its problems, especially during the divorce of Prince Charles and Diana, Princess of Wales, and the public response to Diana's death.
The Queen's stiff upper lip may have been at odds with the public mood at that time but most of the time her poise and dignity played an important role in ensuring the family's celebrity remained within royal bounds.
Despite her reserved manner and flat mode of public speaking, she has been so popular in countries such as ours where she is still head of state, that republican movements do not expect to succeed in her lifetime.
Proposals to replace the monarchy with a homegrown head of state are nearly always predicated on her death.
It seems inevitable, and right, that New Zealand, Australia and Canada will make different constitutional arrangements at that time. Prince Charles is openly relaxed at the prospect.
Republicans in Australia are beginning to agitate for another referendum on the subject. Their last failed because Australians are divided over what kind of head of state should replace the Queen.
A directly elected president would have a popular mandate to rival that of the governing party, without being accountable for taxation and spending as a government is.
The alternative, a head of state appointed by Parliament, would lack independent public standing.
Whatever happens, the public will want to preserve a relationship with Britain's monarch. That is a measure of the respect for this Queen.