It was the American century–in art and entertainment, as in power politics and commerce. Americans invented jazz and rock and roll, abstract expressionism and the skyscraper; we’ve seen the golden age of Hollywood and the rise, for better or worse, of television and the cult of celebrity. In Louis Armstrong’s sky-splitting trumpet, in Audrey Hepburn’s wry bemusement at her own radiance, you could feel the joy of liberation. In the grisly novels of Stephen King, in Charlie Parker’s saxophone leaping and wriggling at the edge of hysteria, you could feel the dread–and find refuge from it. These distinctively American productions blew a hole in the wall between elite and popular culture the size of a drive-in movie screen. They excited and inspired the rest of the world–and ended up covering the planet in cultural kudzu: in the remotest Himalayan village, someone’s wearing a T shirt with the face of Sylvester Stallone.

Early in the century American artists and entertainers were overshadowed by the European masters of high modernism. Picasso fragmented and rearranged the images of representational painting into strange and powerful visions. (His very longevity gives Picasso a claim to the title of artist of the century; he first exhibited in Madrid in 1897, and continued to work almost up to the time of his death in 1973.) In “Ulysses,” Joyce magnified a single ordinary day into a phantasmagoric epic of the thinking mind, and transformed language itself from a mere signifier of information to the novel’s truest subject. Stravinsky and Schoenberg freed music from the constraints of tonality and invented rigorous formal constraints of their own choosing. Yet Americans–particularly African-Americans–were inventing their own hybrid forms of vernacular music: blues, jazz and eventually rock and roll, which has come to be the lingua franca of the world’s youth. Those European modernists recognized America as a locus of energy and innovation; they drew heavily on American popular arts, from jazz to vaudeville to comic strips. When American technology popularized entirely new media–the motion picture, television and the computer–the rest of the world couldn’t refuse.

Technology didn’t just “influence” the arts; increasingly it made the arts imaginable and possible. Movies obviously needed such elaborate mechanical gimmicks as the camera and projector, and mass-production techniques for reproducing and distributing film so paying customers all over the world could make the expense worthwhile. But even the phonograph, a far simpler piece of technology, changed the way musicians thought of their calling. By 1900 Enrico Caruso’s live operatic and concert appearances had made him the great singer of his era; he simply began recording songs and arias in response to demand. But in 1954, when Elvis Presley began his career, he’d seldom if ever performed in public: his aspiration was specifically to make a record. His rockabilly sound was the serendipitous result of fooling around in the studio with two musicians he’d just met; when the resulting recording was played on the radio, this ad-hoc band had to hustle to get together enough songs for a plausible stage show. For Elvis, recording technology, pressing plants, distribution networks and mass-media publicity weren’t peripheral to his art: they were integral to, implicit in, what he did.

The century’s new media–sound recording, motion pictures, radio, television, computers–took some getting used to. Radio was not vaudeville without visuals; movies were not plays staged in front of a camera; television was neither radio nor movie. Initially these media seemed to be neutral containers for the same old content: like photographs, they captured, preserved and transmitted what was out there in the world. But they could also create things that never were. The very earliest moviemakers speeded up, slowed down and reversed projected film to amuse the patrons of nickel theaters. In making “The Execution of Mary, Queen of Scots” (1895) at Edison’s New Jersey studio, cameraman Alfred Clark stopped the film so the actor (not actress) playing Mary could hop away from the chopping block and be replaced by a dummy, which was beheaded in what looked to viewers like real time. Special effects (from crude rear-projected “process shots” to digitized dinosaurs), animated films, seamlessly spliced or overdubbed recordings, radio broadcasts incorporating live and prerecorded material, electronic music, multimedia computer works: these aren’t preserved images of anything that actually existed but pure artifacts of technology.

Yet if technology was esthetically liberating, its costs kept the small fry out. It routinely takes tens of thousands of dollars to make a state-of-the-art CD and millions to make a movie. The recent proliferation of affordable, powerful computers and the growth of the Internet might democratize the high-tech arts. But by the end of the century corporate entertainment conglomerates had largely buried a lively and variegated popular culture under a stultifying, monolithic mass culture: heavily marketed, deliberately disposable and instantly replaceable movies, music, books, television shows and celebrity entertainers. In the hundreds of American country-music recordings of the ’20s and ’30s, idiosyncratic regional styles abound: fans with half an ear could tell a Kentucky fiddler from a Mississippi fiddler. Today the major Hollywood studios determine what plays on cinema screens worldwide.

Recording, publishing and motion-picture companies, of course, were always about making money. The early Hollywood producer Carl Laemmle once recalled the moment of revelation that led him to give up his career as a clothier. “I dropped into one of those hole-in-the-wall five-cent motion-picture theaters,” he told an interviewer. “The pictures made me laugh… I liked them, and so did everybody else… ‘Funny pictures are the thing,’ I said to myself. ‘Charge people and make them laugh’.” That simple quid pro quo evolved into a system of publicity schemes (from cute items in gossip columns to brokered cover deals with major magazines), product tie-ins (from the Shirley Temple doll to the licensed merchandise that accompanies every animated Disney film) and synergistic sweetheart deals with advertisers and manufacturers. The current Austin Powers movie plugs Heineken (the Netherlands), AOL (the United States) and Volkswagen (Germany), while its star, Mike Myers, appears in ads for a British airline. Such revenue-generating entertainment product now dominates the world’s culture. Outside of India and China, Hollywood movies account for more than three fourths of the global market. What’s the non-English-language share of the U.S. box office? Less than 1 percent. It’s not hard to see why: American movies and pop music sell glitz and glamour to a world that’s heartbreakingly short on both. The Depression-era syndrome of housewives in frayed gingham watching Fred and Ginger gliding around some art deco penthouse has gone global.

By the end of the century, the corporate entertainment industry was beating the bushes for fresh, preferably “edgy,” new talents–rappers, independent filmmakers, actors, novelists–making them into instant celebrities, then scouting around for their replacements. True, from Valentino and Nazimova in the ’20s to Prince and Madonna in the ’80s, American culture has been awash in one-name wonders, and periodically lit up by brilliant flameouts: F. Scott Fitzgerald, Janis Joplin, Kurt Cobain. What’s different today is the magnitude of celebrity inflation–“stars” must now be “superstars”–and the speed of turnover. Yesterday’s fresh young thing is tomorrow’s tabloid gargoyle: the process took Elizabeth Taylor 30 or 40 years; her friend Michael Jackson has done it in a decade. But even if nobody remembers the stars of today in 100 years’ time, it’s still been a hell of a show. This has been the century of Irving Berlin and Charlie Chaplin, Diego Rivera and Ernest Hemingway, Edith Piaf and Greta Garbo, Frank Sinatra and Marilyn Monroe, Elvis Presley and the Beatles. If there’s a century that can top that, we’d like to live there. And maybe we will–starting about six months from now. Here’s hoping. But we’ll spend a lot of time looking back.