The election of 2004 is a campaign dominated by a war. But the conflict in question is not Iraq with its horrendous car bombings, the row over the intelligence on Saddam Hussein's supposed weapons and the steady drip of American casualties. Three decades on, America is again wrestling with the ghosts of Vietnam.
To peruse the coverage of the battle for the White House by the US media is like leafing through an old family photo book. There in faded colours is a picture of a youthful, ungrizzled, but nonetheless unmistakable John Kerry, grinning with his colleagues on a navy gunboat, against the green tropical backdrop of the Mekong Delta, circa 1967.
A few days later, another image is all over the television screens of the future junior senator from Massachusetts and present favourite to win the Democratic presidential nomination. The year is probably 1971, by which time Kerry, the decorated hero of the battlefield, has become a vociferous and high-profile opponent of the war. In this photo, you need a highlight to pick him out, sitting several rows back at an anti-war rally. Front and centre of the picture is Jane Fonda, the actress and activist soon to be derided as "Hanoi Jane" by detractors who branded her a traitor for her visit to North Vietnam in 1972.
But the Bush family album is equally in evidence. There is a picture of young George from much the same time as Kerry and Fonda were captured together, protesting against the Vietnam War, in which the young man, complete with military buzz-cut, is standing by a plane. A second photo depicts him in a pilot's suit, under the proud gaze of his smiling father, the then Texas Congressman George HW Bush, later to become the 41st President.
But contrary to appearances, Bush the son was not a "Top Gun" ace, fighting in the skies of South-east Asia. Instead he was performing his Vietnam-era military duties as a pilot in the Texas National Guard, spending his time in the much friendlier heavens over the southern United States, learning how to protect the great city of Houston from possible foreign attack.
President Bush ordered the release of all his National Guard files during the Vietnam War yesterday in an attempt to answer any questions about his military service record, the White House said.
More than 30 years ago, Messrs Bush and Kerry confronted an unpopular war in different ways. Today, the courses they chose have become a central theme of the presidential campaign, entangled in a many-layered debate over patriotism, judgement and sense of duty. At one level, America may finally be getting the Vietnam war out of its system. At another, Vietnam is re-entering America's system, as an inescapable metaphor for America's present war in Iraq.
"Three or four things are playing into this," says Joe Sternburg, who served in Vietnam as a US Marine in 1967 and 1968, and heads the Vietnam Veterans for America association. "Vietnam was not a popular war, and Iraq is turning into an increasingly unpopular war. You have the contrast between Kerry's record and the fact that Bush's military background is questionable. Finally, the military is popular again." In reality, many years have passed since Vietnam veterans were actually disliked, as participants in a war now recognised to have been a mistake. But other doubts lingered. The Gulf war in 1991, with its swift and decisive eviction of Saddam's armies from Kuwait, was supposed to have banished the so-called "Vietnam syndrome", proving America now knew better than to get sucked into a quagmire.
Today, the "Q-word" is everywhere, apropos of the 2003 Iraq war, as the US flounders in search of an exit strategy from a country embroiled in guerrilla war. Yet the military itself is hugely admired. And Vietnam veterans too are basking in reflected glory. As the public mood over Iraq now demonstrates, Americans believe their solders are brave and good men, however dubious the justification of the war in which they are fighting. And for many vets, the experience is cathartic.
"I like it," says Mr Sternburg when you ask him about those Kerry rallies, when the very word Vietnam elicits applause, and the senator's old comrades in arms, "the band of brothers", are cheered to the rafters. You can almost hear him grinning down the phone line.
The most powerful moment of the Kerry campaign perhaps of the entire campaign thus far came two days before the Iowa caucuses, when the candidate was tearfully reunited with a former Green Beret, Jim Rassman, whom Mr Kerry, already wounded, rescued from a river under intense Vietnamese sniper fire. "I guess I owe this man my life," Mr Rassman told an electrified audience.
As the astonishing comeback that started in Iowa has continued, the veterans have become his most precious stage props. "We're a little older and a little greyer," runs Mr Kerry's standard line, "but we still know how to fight for our country."
But it was not always thus. From the outset, the senator built his campaign around his service in Vietnam, calculating it would inoculate him against Mr Bush's record as a "war president", and Republican attempts to cast the Democrats as spineless and unpatriotic. But for most of 2003, the Vietnam lines played to yawns; the candidate seemed to be reading from a script three decades out of date. But then the issue caught fire. The reason may be summed up in a single word: Iraq.
Throughout last year, Mr Kerry struggled to explain why he now criticised a war for which he voted in the now notorious Congressional resolution of October 2002. Questioned on the issue, his answers were nuanced to the point of incomprehensible. Howard Dean thrived, with his broadsides against both Mr Bush and the gutless, hypocritical Democrats in Washington who first supported the war and then, like Mr Kerry, turned against it when the going got rough.
But as matters have deteriorated in Iraq, an old war has been superimposed on a new one, and Mr Kerry's position suddenly makes perfect sense. He, after all, is like so many people in America (not to mention Britain) who, after the apocalyptic warnings from their leaders about the supposedly lethal threat posed by Saddam, felt they had no choice but to support the war. Like them, he is enraged by the apparent fraud on which the invasion was launched, and the shambles that has followed it. And after all, Mr Kerry has been down this path before. Did he not support the Vietnam war to the extent of risking his life there, only to become a leader of the opposition to it?
But consider those other words Mr Kerry famously uttered in 1971 to a Congressional committee investigating the growing mess in Vietnam: "How can you ask a man to be the last man to die for a mistake?" The same haunting question can now increasingly be applied to Iraq. As Mr Sternburg puts it: "Kerry comes across as someone who understands. The Iraq war is coming to look a lot like Vietnam." For George Bush, the Vietnam/Iraq connection works in an opposite sense.
The gaps in his National Guard service played little role in the 2000 campaign. He was, after all, making an attempt to succeed a president who had also wriggled out of the draft. His opponent, Al Gore, had been in Vietnam, but as a reporter with the US Army, not as a frontline soldier. America, moreover, was at peace. But now the country is at war, and the attention paid to the 43rd President's military service has grown in direct proportion to the post-war chaos in Iraq.
By the standards of the time, Mr Bush's behaviour was not especially dishonourable. In a war, two years is an eternity. When Mr Kerry signed up in 1966, Vietnam was still a more or less popular war. By 1968, when Mr Bush left Yale, opposition to the conflict had forced President Lyndon Johnson to step down, and the horrors of battle were being replayed nightly, in colour, on television screens.
A few of his generation and from his background gritted their teeth and went to Vietnam. Others found some medical reason not to go, others went to Canada. But the preferred way was to find a slot in the National Guard. Not surprisingly there were waiting lists for vacancies. So it helped if, like this President, you had the right family connections. Mr Bush strenuously denies it, but the suspicion is strong that he used his family connections to the hilt to enrol as a trainee fighter pilot.
Nor by the standards of the time, was there anything particularly unusual about his patchy duty in 1972 with Guard units in Alabama, where he was working on a political campaign, or about the way he was permitted to leave the Guard six months early to go to Harvard Business School. US involvement by then was winding down in a war almost universally recognised as an undertaking America should never have embarked on.
But Iraq has cast events of the past in a new and harsher light. The pre-war intelligence fiasco and the false claims that American troops would be welcomed with garlands have eroded the credibility that was Mr Bush's most precious asset. Barely six months ago his made-for-campaign ads, landing in a US Navy plane aboard the aircraft carrier USS Abraham Lincoln as it returned from duty off Iraq, seemed to have locked up his re-election there and then. Today the "Mission Accomplished" stunt looks a massive act of hubris, and which becomes more massive still when seen through the prism of Vietnam. The pilot, who chose not to fight a mistaken war when he could have, has been caught play-acting in a war which he ordered and which increasingly seems a mistake.
Mr Kerry is left with the more potent line, that "I know something about landing on aircraft carriers for real". Thus Vietnam and Iraq have subtly merged. Bush supporters reject the notion that only war heroes are qualified to wage war: where would that have left Franklin Roosevelt? But the converse is also true, that those without real war service cannot claim to have a monopoly of wisdom.
Events on the ground in Iraq in 2004, rather than any embarrassing new discovery about Mr Bush's Guard service between 1968 and 1973, will decide how much the controversy will damage him politically. If, miraculously, Iraq does become a success then the whole thing will not much matter. But the more Iraq grows to resemble Vietnam, the argument over what Mr Bush did or did not do in Texas and Alabama 30 years ago will like the dispute over Saddam's WMD be a malign and constant companion along a very hard road back to the White House.Reuse content