'Ladies and gentlemen ... The Beatles!'

It's exactly 40 years Monday since Americans first saw them standing on Ed Sullivan's stage, and writers still barely need to mention that John, Paul, George, and Ringo carry the surnames Lennon, McCartney, Harrison, and Starr.

They were just four irreverent Liverpool lads who were determined to sweep America off its collective feet. But even they never quite figured out how a few minutes on television turned into one of the most significant events in pop-culture history - one that was witnessed by 73 million Americans.

In honor of the Fab Four's US debut, the Monitor asked journalists and DJs who covered the British invasion to reminisce about their experience with Beatlemania, then and during the four decades since Feb. 9, 1964.

"It was just the chemistry, the look, the sound, the songs, the novelty," says journalist and author Ben Fong-Torres, then a student at San Francisco State College. "To hear what Lennon and McCartney were able to do with songs was just beyond me.... I was a fan of theirs pretty much from the first album on," adds Mr. Fong-Torres, a DJ who became one of Rolling Stone magazine's first writers. (He was the editor portrayed in the film "Almost Famous.")

"Cousin Brucie" Morrow, then one of New York's most powerful DJs, proffers the popular theory that the nation was in "depression city." In addition to grappling with the assassination of President Kennedy, Americans were faced with a struggling economy, heightened racial tension, a brewing war, and general unrest - not unlike today, he asserts. "We had nothing to laugh at. And these four guys came over and suddenly we're smiling and laughing again," says Mr. Morrow.

Walter Cronkite could tell Beatlemania was some kind of wild phenomenon, but he calls that post-assassination funk theory "psycho-think." The renowned CBS anchorman notes that the Beatles had already caused mayhem in England, where the populace is usually more sedate - and a country that wasn't experiencing those issues.

"Their music didn't impress me at the time, nor did their performance," Mr. Cronkite says. He admits being dumfounded by the number of worshiping girls in and around the Ed Sullivan Theater on that winter day. But he did "sort of like them," as people, when he met them backstage.

So did the rest of the country - particularly those under 25. "I Want to Hold Your Hand" was already at No. 1 even before they stepped off the plane in New York. Many sibling battles subsequently were fought over clipping rights to a favorite Beatle's likeness, though there were more than enough magazine articles devoted to chronicling their every move. And actual moans were heard when the caption, "Sorry girls, he's married," flashed under Lennon during the Sullivan show.

But the foursome fueled boys' dreams as well. Unlike Sinatra, Elvis, and other teen idols, the Beatles wrote their own songs, and, although they were cut-ups, they were serious musicians, playing their own instruments instead of using anonymous backing bands. On Feb. 10, teens stormed music shops in search of electric guitars.

But many people believed reverberations from Beatlemania wouldn't last a year, much less 40.

Fong-Torres, who later interviewed and toured with Harrison and McCartney, says, "I just felt like they were going to be popular, but I had no clue that they would change the music industry and a good part of the world, and help it define a generation."

Cronkite isn't convinced that the Beatles shook the earth or changed society, but he is surprised at the reaction every Beatles event still evokes today. "This anniversary proves that the music was long-lasting," he says.

Fong-Torres attributes our continued interest to three factors: the timeless quality and substance of the music itself; the fact that people who grew up as Beatles fans now control the media; and canny, well-timed marketing efforts, including exploiting anniversaries by releasing new material or refueling interest by the use of a song in a film For example, this anniversary was marked by the DVD release of "The Beatles: The First US Visit."

Morrow observes that people usually remember what they were doing on historic dates marked by tragedy. Anyone who's old enough is simply expected to have an answer to that "where were you ..." question.

But the Beatles gave the post-World War II generation a cultural marker defined by a happy moment: Feb. 9, 1964, just after 8 p.m. Eastern time, when Ed Sullivan said, "Ladies and Gentlemen - the Beatles!"

And still, we love them. And you know that can't be bad.