As the American election battle moves into its closing stages, events more than 30 years ago are, once again, overshadowing the campaign - except that the scrutiny has moved from John Kerry and his war medals to whether George Bush shirked his duties and disobeyed superiors during the National Guard service that enabled him to avoid being sent to Vietnam.
The latest instalment of a long controversy has been stoked by the release of new memos from Mr Bush's commanding officers in the Texas Air National Guard covering his service - or lack of it - between mid-1972 and mid-1973.
At the same time, Ben Barnes, who was lieutenant governor of Texas when the future President won his coveted position in the Guard in 1968, has admitted giving the younger George Bush a helping hand, at the request of friends of the powerful Bush family.
It comes as Mr Bush has, for the first time, established a clear lead in the polls, with a six or seven point advantage over his Democratic challenger.
State by state surveys also show him opening similar leads in Ohio and Missouri, two of the swing states likely to determine the result on 2 November.
In a CBS interview on Wednesday evening, Mr Barnes - who has contributed money to the Kerry campaign - admitted he had pulled strings on behalf of Mr Bush, "preferential treatment" which he now regretted. Those charges, however, have been aired before. Potentially more damaging are memos from Lieutenant Colonel Jerry Killian, suggesting Mr Bush disobeyed orders and that the string-pulling on his behalf continued into mid-1973.
In one memo, dated 1 August, 1972, Colonel Killian says he ordered that "1st. Lieutenant Bush be suspended from flight status due to failure to perform to USAF/TexANG standards, and failure to meet his annual physical examination ... as ordered." More than a year later, Colonel Killian - who is now dead - wrote in a memo on 18 August, 1973 that he was under pressure from the commander of the Texas Air National Guard to "sugar coat" his evaluation of Mr Bush's performance for the year to mid-1973. That time includes the months when Mr Bush was supposedly with the Alabama National Guard, but by all accounts failed to show up.
The point is being hammered by a new independent anti-Bush group 'Texans for Truth,' that is running TV ads in several swing states. In it, a pilot in the Alabama guard states that never once saw Mr Bush, and would certainly have remembered if he had.
Mr Kerry himself is maintaining a statesman-like distance from the dispute.
But other Democrats have seized on it to get in some blows of their own after the attacks on Mr Kerry's veracity from the Swift Boat Veterans for Truth group. These undoubtedly contributed to what the candidate yesterday acknowledged had been "a bad August," confirmed by his recent slide in the polls.
"George Bush's cover story on his National Guard service is rapidly unravelling," Terry McAuliffe, the Democratic Party chairman, declared, calling on the President to explain "why he regularly misled the American people, and who applied political pressure to have his performance reviews 'sugar-coated.'
But the broader impact of the controversy is doubtful. "I don't think it will be nearly as damaging [as the Swift boat affair was to Kerry]," Bill Schneider, a political expert at the American Enterprise Institute, said. "Bush didn't premise his campaign on Vietnam like Kerry. Also he's been President for four years. People are judging him on his record, not what happened more than 30 years ago." Indeed, Bush's sketchy record in the Texas National Guard came up during the 2000 campaign, but never developed into a major issue - not least because Democratic criticism of his failure to serve in Vietnam was swiftly countered by Republicans pointing out how President Bill Clinton avoided the draft . Bush's service, or lack of it, briefly became an issue last year as well, immediately after the invasion of Iraq, but again quickly from the news.
This time the attacks are more co-ordinated. But as Norman Ornstein, another AEI expert noted, the real danger was if a "smoking gun" emerged, proving that Bush had actually lied in his account of events. "
Then his credibility could be damaged. Otherwise this won't change the minds of Bush supporters." Another smoking gun - the subtext issue that few directly raise - is drugs, and the rumours that one of the reasons Mr Bush skipped the medical was because of cocaine use. Those charges are hotly denied by the White House, though Mr Bush has acknowledged he made "mistakes" during a largely misspent youth.Reuse content