Ten years ago, 29 men, women and children and two unborn babies were murdered and more than 200 people were injured and mutilated when the Real IRA exploded a 500lb car bomb in the crowded high street of Omagh.
Omagh was the biggest loss of life in a single attack in the Troubles
In the hunt for the perpetrators, Tony Blair said they would be "pursued to the utmost" with the then Northern Ireland secretary of state and the chief constable of the Royal Ulster Constabulary both pledging that "no stone would be left unturned".
The fact that the crime was committed north of the Irish border, but planned and executed in the south where the key suspects lived, was not seen as an obstacle.
"We are at one as to what is required," then Irish Prime Minister Bertie Ahern told the Irish parliament.
There was "complete unity of purpose between the British and the Irish authorities", said Mr Blair; cross-border co-operation between the RUC [now the Police Service of Northern Ireland] and Garda Siochana would be "unprecedented".
None of this has come to pass.
As we mark the 10th anniversary of what Mr Ahern described as "the most evil day in years", not a single member of the 15 or more strong gang responsible for it is in jail for any offence connected with Omagh.
In reality the two police forces north and south of the border had different procedures, laws and rules and they were unable to agree a joint protocol. The inquiries were effectively parallel but separate.
After six months, the Garda Siochana did charge veteran republican Colm Murphy with conspiracy to cause explosion; he was convicted but, following an appeal, even he is free again pending a retrial.
A memorial garden is being opened on the 10th anniversary
Thereafter, both inquiries lost momentum.
In England and Wales, it was increasingly the practice of police forces to take stock with a "murder review" if no-one had been arrested within the first four weeks.
A review aims to ensure that the investigative thrust is headed in the right direction and to provide a course correction if it is not.
In the case of the Omagh bomb, the Garda Siochana refused point blank to hold one and 19 months passed before the RUC began theirs.
It was the first of its kind in Northern Ireland and found that many problems had by then accumulated: lack of resources; a failure to exploit the evidential capabilities of the computerised Home Office Large Major Enquiry System (known as Holmes); an absence of a co-ordinated approach to intelligence analysis; a confused command structure.
In December 2001, the newly appointed Northern Ireland Police Ombudsman Nuala O'Loan blamed the then Chief Constable Sir Ronnie Flanagan for the inquiry's failure to put the bombers behind bars.
O'Loan accused Flanagan of "a failure of leadership", saying: "The victims, their families and officers of the RUC have been let down by defective leadership, poor judgement and a lack of urgency."
Sir Ronnie passionately disagreed. "I would not only resign, I would publicly commit suicide if I felt this... to be fair," he said.
But Sir Ronnie was manoeuvred into retiring early and in May 2002 a new head of the inquiry was appointed, Det Supt Norman Baxter.
In the months before Omagh, republican dissidents had exploded other bombs.
Sean Hoey is the only person to face murder charges over the bombing
Baxter believed all these incidents were linked and focused his enquiries on their timer power units [TPU] which sent current to an electrically-fired detonator.
Scientists reported that they found DNA matching that of an electrician from South Armagh, Sean Hoey, in the TPUs of four devices that failed to explode.
Although no DNA was recovered from the Omagh bomb because it had exploded, Baxter believed that together the four failed bombings, and other bombings linked to them, "produced an evidential rope" which proved Mr Hoey had made the timers for all of them, including Omagh.
The DNA had been discovered using a new technique called "low copy number DNA".
At his trial, Mr Hoey's barrister accused two officers of lying, the police and Forensic Science Service of slapdash storage and labelling of exhibits, and explained the presence of Mr Hoey's DNA through innocent contamination, for example through exhibits taken from Hoey's home.
Last December, the judge acquitted Mr Hoey of all 58 charges.
However, all may not be as it seems.
The Police Ombudsman has been conducting an inquiry of his own into whether the officers did, in fact, lie.
A recent report for the Northern Ireland Policing Board by Sir Dan Crompton, former HM Inspector of Constabulary for the North of England and Northern Ireland, has also paid "tribute" to how Mr Baxter - now detective chief superintendent - has "discharged this heavy responsibility" of heading the inquiry "over six years."
And yet for 10 years the police have had very precise intelligence as to who the culprits are, as Panorama made clear in October 2000 when I named four of them with "Who Bombed Omagh?"
Do the criticisms of two extensive and expensive police investigations adequately explain why no-one is in jail today?
Personally I don't think so. Next month, for Panorama, I'll be returning to the subject of Omagh to explain why.