Opera: And here, with the latest news - sung to you in heroic couplets - is... the opera composer

Opera? It's just a load of nonsense about dead Greek heroes, gypsy girls and thwarted lovers. Well, not since John Adams gave President Nixon and Chairman Mao something to sing about. Mike Ashman charts a growing trend to set the headlines to music.

Nixon in China, 1972: election year in the States. To help Richard Nixon win a second term, his right-hand man and foreign affairs "adviser" Henry Kissinger sets up a ground-breaking trip to the People's Republic of China in the hope (but not the certainty) of meeting Chairman Mao-tse- tung. During this supposedly major world-peace initiative, the Nixons (Richard and wife Pat) and Kissinger met Mao and Premier Chao-en-lai, saw the Great Wall of China and one of Madame Mao's politically correct (but Hollywood-ised) ballets, and produced a fairly meaningless communique. The world's media gobbled it up.

Nixon in China, 1984: a good title for an opera. So at least thought American poet Alice Goodman when she was telephoned in Cambridge (UK) by her old Harvard contemporary, director Peter Sellars (who conceived the idea), to be told that was the name of the opera she was to write for composer John Adams. "Oh - and it must be in couplets." Goodman agreed.

The opera was premiered in October 1987 by the Houston Grand Opera, whose general director John Gockley has made a speciality of creating new operas with contemporary settings. It was an instant and spectacular success - not least with audiences. A sizeable number of performances followed in America and overseas. In the UK, it followed a decade's pattern for important music and theatre premieres by playing only in Edinburgh.

Nixon in China, 1998, and John Adams is in town for the long-awaited London premiere of his first opera, to be given this Sunday - albeit in concert form only - as part of the Barbican's "Inventing America" festival.

"What refreshes me about it," he says, "and makes it still interesting and tolerable after 10 years is that we didn't use it as a vehicle for easy satire. The wit is more subtle, less in the caricaturing of Nixon than in the use of operatic conventions to tell this very, very contemporary and particularly American story.

"The idea of having Madame Mao - this woman who had started life as a movie star, had gone on to become Mao's girlfriend, later his wife, had become this malevolent force behind the Cultural Revolution and had used the arts, particularly ballet, to embody her own political beliefs - sing her big aria as a da capo, coloratura, `Queen of the Night' aria ending the second act as if it were a French opera - that's where the wit and satire is in this opera, not in attacking Nixon.

"I wanted it in couplets to give it a kind of arcane quality. I didn't want them to be speaking in mere prose. I wanted to give it that heroic scale that you get when you read Homer, Virgil and Spenser. It's a great thing to have Richard Nixon or Henry Kissinger singing in heroic couplets.

"It was very hard for me to untangle the Nixon of his more honkingly ridiculous moments - his Chequers speech, his famous "I am not a cook" - from using him as a vehicle for examining major issues of our time. But this story had the clash of the cultures, the clash of the economies. Here was America, the `most powerful country in the world', with our overly inflated image of our own rectitude, coming face to face with Communist China, which, at least in my childhood, was this implacable, unknowable, sinister force - just like a dark force out of Dante."

In 1991 came another opera from the same team - Adams, Goodman, Sellars - about the terrorist hijacking of the cruise ship Achille Lauro and the killing of the Jewish tourist, Leon Klinghoffer. "The Klinghoffer story again was fantastically resonant," says Adams. "It dealt with the Middle East - one nation aggressing another, or, if you're on the other side, the threat of terrorism and assassination. On the other hand, it was a story that could have been located somewhere in Genesis. It seemed aeons old; it could have been written on a tablet discovered somewhere in the Sinai Desert.

"We treated it very much that way. I asked for these big choruses to give a feeling of oracular scope to the opera. They would sing about the natural world - or they would sing about Hagar and Ishmael. Then the next minute we're right up in 1984 - Americans on a cruise ship and Palestinian guerrillas scaring everybody half to death. So there's a wonderful dissonance happening, theatrically."

The British critic Andrew Porter, an early Nixon in China enthusiast, considers Gaveaux's Leonore - the model for Beethoven's Fidelio - a possible early example of an opera premiere where, as Adams puts it, "some of the characters could have attended had they so wished". (And perhaps elderly Swedish courtiers could have got to see Auber's or even Verdi's much-censored settings of the murder of Gustavus III.) "I don't think that a piece has to be necessarily political, or to be torn from the headlines, to be a success - but I think that's a very interesting way to go. In the case of Nixon and Klinghoffer, both of these operas dealt with issues that were very much on our mind and probably on our self-conscious."

Nixon and Klinghoffer have succeeded for more old-fashioned reasons than their "contemporary" settings. Kent Nagano, a long-term Adams champion who conducts this Sunday's LSO performance of the former, draws attention to their purely musical strengths. Alice Goodman remembers the work that she put in with Adams and Sellars to make their material suitable for an opera.

The trend that Adams and his collaborators appear to have started often extends no further than a shared subject matter about public figures only recently dead. America has seen Stewart Wallace's Harvey Milk, Michael Daugherty's Jackie O and Anthony Davis's X: The life and Times of Malcolm X; Germany, Gerhard Rosenfeld's Kneeling Down in Warsaw (about Willy Brandt); and Britain, Thomas Ades's Powder Her Face (about the Duchess of Argyle, of "headless man" fame).

Jackie O, some impressions of the former First Lady's post-JFK life, is a "pop" opera, well described by librettist Wayne Koestenbaum's own advice to "think Roy Liechtenstein". Daugherty's interest in "music inspired by American popular icons" has already taken in Elvis Presley, Desi Arnez, Superman and the wonderfully named Le Tombeau de Liberace, a piano concertino. Jackie O (released on CD by Decca's Argo label last year) does not really aspire to use historical characters as "vehicles for examining major issues of our time". Its collagey, even college-y, parade of stars - Liz Taylor, Grace Kelly, Andy Warhol and Maria Callas (who sings as a mezzo to indicate the state of her vocal health) - is reminiscent of Koestenbaum's cult book, The Queen's Throat, a wry examination of opera's attraction for homosexuals.

Gay opera fans cruising at the back of the Old Metropolitan Opera House - "men without wives" who talk about a mysterious girl called Tessy Tura - intrigue the young Harvey Milk in Act 1 of Stewart Wallace's 1995 opera. With its three American co-premieres and a recording (under Donald Runnicles) imminent, someone may have been hoping for another Nixon. The subject was suggested to its authors by the British director John Dew, who staged Nixon's German premiere and commissioned Kneeling Down in Warsaw for his Dortmund opera house.

Michael Korie's often witty but rarely resonant libretto, "based on fact and fiction", works on the life of Harvey Milk, a Jewish businessman who came out from what the opera calls his New York closet to become San Francisco's first openly gay elected civic official. Milk and his chief, Mayor Moscona, were assassinated by a paranoid right-wing colleague in 1978.

Wallace's and Korie's work keeps a reasonably open view about what could easily become a simple them (right-wing bastards) and us (left-wing angels) story, handing some lovely music to Milk's murderer, Dan White. Harvey Milk borrows a crowded location schedule (New York opera house and "Stonewall' riots, several quarters of San Francisco) from the TV documentary on which it is partly based, and tops it off with good old Hollywood tricks (starting with Milk's assassination and flashing back; introducing a "Messenger" at the end to take dead Harvey "to a high place" to watch his own funeral). It's ingenious, but it remains in the realm of what the US press have called the "docu-opera".

"Docu-operas?" protests Adams. "I've been blamed for that and I want to say right here publicly, `I'm out of the business!' That term is a pejorative way of dismissing what I think is a very vital and meaningful way of dealing with the art form. Using contemporary events - or, as I call it, contemporary mythology - is absolutely a bona fide point of view. If I do another opera, I may very well do that again. Opera can deal with big mega-issues about human destiny, about political forces and opinions across the globe in a way that no other art can quite do."

`Nixon in China': 7pm Sunday, Barbican Hall, London EC2 (0171-638 8891)