Leading article: Icons for all

What are the qualities of a "gay icon"? According to the panel behind the latest exhibition at the National Portrait Gallery, they include what you might expect: talent, wit, courage etc.

But a gay icon does not, it would seem, need to be gay. Among the individuals who will be featured in the show are the former South African president Nelson Mandela and the Russian cellist Mstislav Rostropovich.

Of course, there is a tradition of straight gay icons, stretching from Judy Garland to Smith in Sex And The City. But it is not only gay people who admire Mandela, or adore Garland for that matter. What then makes this a show of gay icons, rather than just icons?

Let us defer to the wisdom of Oscar Wilde who pointed out that "consistency is the last refuge of the unimaginative". And, as if to prove this point, Wilde – a gay icon if ever there was one – will not be in the show.