KEY POINTS:
To paraphrase the opening line of Sgt Pepper's Lonely Hearts Club Band, it was 40 years ago this week. In January 1967 a crowd of between 10,000 and 50,000 - depending on who's telling the story - gathered in Golden Gate Park, San Francisco, for a Human Be-In, a blend of rock concert, arts festival and protest meeting that introduced the hippie phenomenon to a puzzled world.
The Grateful Dead and Jefferson Airplane provided the music, beat poet Allen Ginsburg and LSD advocate Timothy Leary, author of the hippie credo "Turn on, tune in, drop out" made speeches, and a parachutist showered the crowd with psychedelic drugs.
Within a few months Scott McKenzie released the hippie anthem San Francisco (Be Sure To Wear Some Flowers In Your Hair) and the Beatles brought out their groundbreaking Sgt Pepper's album before floating off to India to absorb the spiritual essence of Maharishi Mahesh Yogi.
The Summer of Love was under way; the counter-culture was on the march. Notwithstanding silly talk of "the revolution" the world would never be quite the same again.
Social conservatives would argue much of what's wrong with society today - their list would include drug use, promiscuity, pornography, apathy, and bad manners - can be traced back to the Summer of Love.
Progressives would respond that the counter-culture's creativity, energy and idealism gave Western culture an almighty shot in the arm, focused attention on the environment, and provided the impetus for the great anti-discrimination drive to secure equal rights for women, racial minorities, and gays.
What is certain is that the Summer of Love didn't usher in an era of peace and understanding. They might have been making love, not war in Haight-Ashbury but elsewhere in the world all hell was breaking loose.
In January 1968 North Vietnam launched the Tet Offensive involving 70,000 regular troops supported by Vietcong guerrillas. Although a military failure, the offensive's scale and ferocity surprised and unnerved America whose will to prevail began to crumble.
In March United States soldiers massacred around 500 villagers, mostly unarmed women and children, at My Lai. Despite the US Army's attempts to cover it up the story broke the next year, fatally undermining America's claim to have right on its side.
In April Martin Luther King was assassinated, triggering riots in 100 American cities. In June Bobby Kennedy was assassinated while campaigning for the presidency.
In August anti-war protesters gathered in Chicago for the Democrat Convention were systematically brutalised by a massive contingent of police and National Guardsmen.
Under siege at home and abroad, America seemed to be turning on its young, an impression that was reinforced eight months later when six students protesting against the invasion of Cambodia were shot dead by National Guardsmen at Kent State University.
Also in August tanks and troops from the Soviet Union and its Eastern European satellites entered Czechoslovakia to depose the reformist government and crush the so-called Prague Spring. The bitter divide between the US and the USSR was wider than ever although the flight-time of their nuclear missiles was down to a matter of minutes.
The following August a tiny hippie cult led by Charles Manson butchered the heavily pregnant actress Sharon Tate and six others in Beverly Hills.
It had taken just two and a half years for the movement to be hijacked by psychopaths and for the inherent contradiction between its core messages of universal love and revolution to give rise to savagery with a rock'n'roll soundtrack.
1969 also saw the release of Easy Rider, starring Hollywood hippies Peter Fonda and Dennis Hopper. As well as having a profound effect on society - Hopper claimed it turned America on to cocaine - and ushering in a new era in Hollywood in which the auteur-director was king, the movie was enormously successful: made for (in 1969 money) US$500,000 ($720,000), it grossed $US19 million in its first year and US$50 million within a decade.
Fonda and Hopper shared the screen-writing credit with Terry Southern. The author of the cult novels Candy and The Magic Christian, Southern was "the most profoundly witty writer of our generation" according to Gore Vidal and "the hippest guy on the planet" according to the New York Times.
With the likes of Marilyn Monroe, Sigmund Freud and Albert Einstein, he's a face in one of the 20th century's most famous crowd scenes - the Sgt Pepper's cover. (He's the guy in sunglasses.)
Fresh from writing the script for the classic anti-war black comedy Dr Strangelove, Southern was one of the highest-paid screenwriters. He was also a bohemian soul and Easy Rider was a shoestring production so in the hippy spirit of share and share alike, he waived his usual fee.
When the movie became a hit, Hopper and Fonda dismissed Southern's contribution, claiming he'd withdrawn early on leaving them to write the script. (For the record the only original copies of the script that have ever surfaced are clearly Southern's work and neither Hopper nor Fonda has written anything of note since.)
The Hollywood hippies got rich. Southern died in poverty.
