The Clinton trial shows that American ideology is paranoid. Even a warmonger like JFK was seen as a threat

The Ambassador Hotel in Los Angeles is to be demolished. "I don't understand," says Mitzi Mogul of the Art Deco Society, "why in LA we tear down our monuments to build shopping malls; it's sickening." The answer is that a shopping mall is one of the American century's twin symbols. The other is an image of homicide: the mushroom cloud over Hiroshima, the piled dead of Vietnam, the victim of an assassin's bullet.

The Ambassador Hotel can provide the latter, although its other ghosts offer nostalgic relief: Scott and Zelda Fitzgerald, who set fire to their room, and Albert Einstein, who complained about room service. The wonderfully kitsch Cocoanut Grove nightclub saw the likes of Rudolf Valentino, Marilyn Monroe and Elizabeth Taylor at play, and the first Oscars were presented here.

I drove to the Ambassador on the hot night of 4 June 1968, after the polls had closed in the California primary to select a Democratic candidate for president. I had just returned from two weeks on the road with Robert Kennedy, having flown with him from the San Joaquin Valley. Mine was one of his last interviews. He was button-eyed with fatigue, with Ethel, his wife, sleeping soundly beside him. As we took off, the windows were filled with Mexican-American faces from the vineyards, where they worked in peonage; many were crying with joy at the sight of the candidate.

"These people love you," I said. "How can you help them?"

"I can be president of the United States."

"So can Hubert Humphrey or Richard Nixon . . ."

"They can't be President Kennedy . . ."

His rabbit smile dismissed his weariness, and he spoke about "tapping people's dreams". I said I had observed his political duplicity, as he played to middle-class fears of black and brown people. He replied with a non sequitur from Bernard Shaw about everything and anything being possible.

When I arrived at the Ambassador Hotel, his LA headquarters, the following night, I pushed downstairs and through the crowd in the ballroom, where I met a Kennedy volunteer, Susan Harris, who got me a beer by taking a short cut through the kitchen. "There's a little guy in there who keeps looking at me kind of funny," she said, "like he's waiting around for something." It was Sirhan Sirhan, standing with his hand in his jacket, holding a revolver; nobody sounded the alarm.

Shortly after midnight, a delirium of cheers greeted "the next President Kennedy". The candidate thanked "this great and compassionate country", jumped down from the podium and headed for the kitchen, the short cut to the car park. I was be-hind him. The little man in the corner took his hand out of his jacket, aimed and fired from three to four feet away. Kennedy shouted, "No!" One of five bullets sang past my left ear and hit a woman beside me. Lying with his arms outstretched, Kennedy uttered noble last words: "Is everybody all right?"

The coroner concluded that Kennedy had been killed by a bullet fired point-blank at the back of his head. I told the FBI it was impossible for Sirhan to have fired this. All the other witnesses concurred. In the early hours that followed, I met a young woman who had seen a couple running from the hotel, with the female saying, "We've shot him!" This was the woman in the "polka-dot dress" who was never apprehended. There is a tape-recording of the detective leading the investigation, imploring his men to stop pursuing the couple. The FBI found more bullet holes than there were cartridges in Sirhan's gun.

A 1992 Channel 4 investigation by Chris Plumley and Tim Tate produced impressive evidence that strongly suggested that Sirhan - a Palestinian with a "motive" for wanting to kill the Israel-supporting Kennedy - was merely a stooge, a patsy. Nothing is proven, and the truth remains illusive, as in the welter of dissenting evidence surrounding the assassination of John Kennedy almost five years earlier. (When I went to Dallas shortly afterwards, the trajectory path of one of the bullets fired at John Kennedy was still engraved in Dealey Plaza and could not have been fired by Lee Harvey Oswald who protested, moments before his own murder, that he was a "patsy").

What is certain is that, deep within the "national security state", both Kennedys were seen as a threat to the American imperium. This was patently absurd; indeed, the opposite was true - John Kennedy was a warmonger, and Robert Kennedy, who had worked for the witch-hunting Joe McCarthy, saw an opportunity in 1968, the revolutionary year, and promised to end the war in Vietnam, which he had supported. There is little doubt he would have beaten the counter-revolutionary candidate Richard Nixon for the presidency. Would he have stopped the war? I doubt that. It continued for another six and a half years.

These memories provide a clue to the reasons for the current circus in Washington, the impeachment trial of Bill Clinton. Its significance is that, once again, a veil is lifted on the paranoia of American ideology. The fundamentalists are represented by the religious zealot Kenneth Starr, Clinton's special prosecutor, and a brace of primitive Republican senators, who regard Clinton as a dangerous liberal. This is both a measure of their dementia and their fanaticism. For Clinton has strained every fibre to establish his reactionary credentials. He has abolished the last of the Roosevelt welfare reforms, bombed Muslims as often as possible and approved the biggest war budget since Ronald Reagan. As for the rest of us, we might take heart from having almost reached the new millennium without our imperial masters having blown us to bits.

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