Poor opera! And yet not so poor. This unloved creature may be quite irrelevant to 95 per cent of the population, but it gets bags more state subsidy than any other art — about a fifth of the whole cake, in fact.

Every six months or so opera surfaces from its undersea lair, like a Bond villain, to enter public consciousness — generally when it’s been naughty. A director put something stupid on stage at Covent Garden and the audience struggled awake to bay its disapproval. A tenor with wandering hand trouble has been banned from ever again opening his mouth. A soprano said it was just so wrong that female characters keep getting killed on stage (but she’s just accepted the role of Carmen, bless her).

Occasionally, opera’s panjandrums are wheeled out to “popularise” it, with disastrous results. When the bosses of British opera houses were asked to say why it is so great, they came out with: “We experience emotional and imaginative truths not in private, as we may do with a poem, but in the company of strangers with whom we tacitly share these profound and transformative cultural experiences.” Anyone fancy a pint? Even at crush bar prices?

Yet notwithstanding the low-rent civil-service rejects who run its cushily subsidised billets, opera has one big thing going for it: it’s really very good. It can do things no other human endeavour can even dream of approaching. When Richard Rodgers used a little Austrian folk-tune to undo the Nazis in The Sound of Music, he was consciously joining his music-theatre brothers from Monteverdi to Mozart to Wagner in proposing the nature of music as a moral force, a weapon that can make us fall in love, but can also smash down the gates of the Underworld to “make hell grant what love did seek”, as Milton wrote of Orpheus and his lute.

Music’s nature as metaphysical argument, as philosophy, as moral quality, comes in any number of packages: Rossini, generally supposed a frivolous exchanger of spun notes for cash, makes the case that a soprano emitting impossible, cartwheeling cascades of notes can physically incarnate the concept of human joy; Donizetti, whose music turns an anecdote about stupid peasants getting drunk in the afternoon into a parable of human liberation; Beethoven’s furious insistence in Fidelio that enough C major chords can beat down the strongest prison walls.

The reason that opera can even think of doing this is not because of its difficulty but the exact opposite: because it’s the most direct, least sophisticated form of musical communication. Sure, much of the opera world likes to present itself as the acme of high culture, but that’s just sand in your eyes: the truth is that proper, heavy musicos have always derided opera precisely because of its cheap populism and easy apprehension. In a world where music is the universal language, opera has accomplished the unlikely feat of making itself seem mimsy and pointless. But where has recent visual art or theatre matched the ambition and accomplishment of the Barbican’s Einstein on the Beach, Berlioz’s Benvenuto Cellini at ENO, a couple of massive instalments of Karlheinz Stockhausen’s insanely ambitious Licht cycle staged in Birmingham and the Festival Hall? You probably missed them: nearly everyone did.

It doesn’t have to be this way. Opera certainly needs critics but it doesn’t have to take any criticism for being what it is.