AMID all the celebrations, the rousing choruses, the street parties and the services, amid all the flummery and the flattering, there sits an enigma. Just exactly who is the Queen?

The unknowable nature of our monarch is probably her greatest asset, and in this celebrity-obsessed age, in which glossy magazines are devoted to spilling the secrets of ‘famous’ people you have never heard of, the most famous of them all remains a puzzle.

The Queen is familiar to everyone yet little is truly known about her; and surely this is just the way she wants it.

Even those among us who struggle to call ourselves monarchists have to admit she carries off her role well and with dedication, doing what needs to be done, without giving anything much away.

Once we on the vaguely disgruntled left might have rallied to the republican flag, but is it really worth all the wasted energy, all the indignant hot air raised to no likely purpose?

Even though my head tells me that the monarchy is a symbol of unelected privilege, my heart sighs with the thought of bothering to get cross about it.

Well, the Queen certainly remains highly popular as this week’s Diamond Jubilee celebrations have shown.

Is it fair to suppose that her continuing popularity is at least in part down to her inscrutability and her carefully contained nature?

Those who take a keener interest in these matters than your columnist suggest she can be modern in outlook in some senses. Yet at heart, there also appears to be an old-fashioned remove about Her Majesty.

Recent spilt beans from a former royal chef were taken as evidence that the Queen eats carefully and in moderation, which is the keynote for how she conducts her public life. Any attempt to surmise what the Queen really thinks about anything is likely to run aground on the shores of her reticence.

We are as likely to know her through dramatic portrayals – heck, we probably know more about Helen Mirren as the Queen than we do about the Queen in that role – as we are through her own thoughts. This has proved to be her greatest strength, and possibly hides a steelier side.

Only after the death of Diana did she falter, finding herself seemingly out of step with the emotional incontinence of the moment.

In general, her containment stands in marked contrast to the behaviour of her eldest son.

Prince Charles has spent much of his public life offloading his opinions about almost everything, summoning up a catalogue of mostly Conservative views, sprinkled with a few cranky passions.

Whether it is his views on architecture or alternative medicine, or his past marital problems, we know as much as we need to know about Prince Charles.

When or if he becomes King, he will present a different proposition to his mother. We know so much about him that it will be difficult to regard him as a contained individual who keeps his thoughts and opinions to himself.

One way in which ordinary people try to understand the royals is to superimpose their own ordinariness on to the Windsors. So it is that the Queen becomes the family grandmother who attempts to smile sweetly at family gatherings – although she does have to attend an awful lot more than the average gran.

Sometimes, and unsurprisingly, the cameras catch a look of boredom or weariness. What, we wonder, must she really think of the big dos thrown in her honour; and did she honestly enjoy what, from snippets at least, appeared to be an odd and rather toe-curling concert on Monday?

We won’t ever know, of course.

Columnists faced with an unavoidable ‘date’ with the Queen can only guess along with the rest. Or, like a leading columnist on The Sun this week, do what columnists sometimes do and make it all up for comic effect, pretending to portray the Queen’s inner thoughts.

Such exercises can be fun, but they don’t get us any closer to the enigma.

As for the future, a change at the top will show whether it is the monarchy which is popular or the monarch.