Now that the departure of Neil Lennon has been announced, it is time to ask why enlightened and progressive Scotland treated him in such a vile manner in each of the dozen or so years he spent with us. The resignation of a Celtic manager ought only to be the subject of scrutiny on the sports pages, with his success rate and football legacy being picked apart and compared with others who have occupied that seat. Such, though, has been the universal hatred to which this young man has been subjected in every part of Scotland that any interpretation that fails to analyse why is immediately rendered meaningless. Neil Lennon is, quite simply, the bravest man in Scotland.

Lennon was that rare thing in the world of team sport, a highly skilful player who immediately went on to become a very successful manager. From 2000, as his career in Scotland progressed, it soon became apparent that he was being abused and vilified at almost every away ground he visited. Something other than football rivalry was being expressed here and it was becoming ugly to behold.

In matches against Rangers FC, then Celtic's oldest and fiercest rivals, the abuse was almost unbearable and on one occasion Lennon's manager, Martin O'Neill, put a fatherly arm around his shoulders and marched him halfway up the pitch as if to say: "I know what this is about, but this is my son and we will always support him." Lennon, you see, is a Catholic from Northern Ireland. He has red hair and a belligerent onfield demeanour that brooks no compromise. He never backs down. And then of course, he played for Celtic FC. For some in Scotland, this was a toxic cocktail that deserved a violent response.

In his time at Celtic, Neil Lennon was the victim of almost a dozen assaults and attempted assaults. On one occasion, he was kicked to the ground by two assailants outside his favourite wine bar in one of Glasgow's most desirable neighbourhoods. Most famously, he was attacked on the pitch in Edinburgh by a supporter of Heart of Midlothian. The incident was witnessed by millions watching live on Sky TV. In what must have been a world legal first an Edinburgh jury subsequently cleared his assailant.

Three years ago, two men from Ayrshire tried to blow up Lennon and his family by sending him a parcel bomb. A judge convicted them of a lesser charge. Others had attempted to send him bullets in the post. He was forced to stop playing international football for his beloved Northern Ireland because he and his family began to receive death threats immediately following his move to Celtic.

During Lennon's 13 years in England as a player for Manchester City, Crewe Alexandra and Leicester City, there hadn't been a single controversial incident involving him. As soon as he pulled on the green and white hooped jersey, he became a marked man throughout Scotland and subjected to a persistent and egregious litany of hate. Since 2011, he and his family have received round-the-clock police protection at home and at his children's school. During this time, Lennon was badly let down by every major organisation in Scotland that would normally have been expected to intervene as this extraordinary campaign of personal vilification was being played out before them. Let none be in any doubt about this: Lennon was hated for his religion and for his country of origin. Too many Scottish football writers either chose to ignore what was happening or, worse, tried to justify it by saying that, by dint of his belligerent demeanour, he brought much of it upon himself. They conveniently overlooked the fact that Lennon had an exemplary disciplinary record and never criticised opposing teams or managers. Away from football, he lived quietly and openly in Glasgow's West End, where he enjoyed the company of supporters in the wine bars and restaurants of that neighbourhood.

The Scottish government simply chose to look the other way while a migrant worker in Scotland was being racially abused in front of them and the Scottish Football Association refused to intervene. Indeed, on the only occasion that they did so, they hit Lennon with an extraordinary ban as punishment for reacting angrily, but not violently, to something uttered quietly by Ally McCoist, his Rangers counterpart. You got the impression they had been waiting to do that for some time.

Meanwhile, the government, in a gross act of cowardice, decided to use that incident to show that it cared by organising an utterly worthless and meaningless summit on sectarianism. Yet it had nothing to say about the campaign of abuse that Neil Lennon endured in this country. No anti-racism body ever came to his aid. There are some who claim that Scotland remains an anti-Catholic country, but it's not really.

Nor is this about Rangers FC, that once mighty bastion of the Scottish Protestant hegemony. They have routinely been employing Catholics for years and participate fully in anti-sectarian projects. Rather, there is still a sizable remnant of Scots who cling stubbornly to old ideas of religious and cultural supremacy and who regard the Irish as an inferior race.

The pillars of their existence were the Church of Scotland, the Conservative party and the reserved professions where Catholics were once told politely they need not apply. These have all either disappeared or been rendered meaningless. The Catholic Irish, meanwhile, have emerged confidently from discrimination and deprivation to play a full role in modern Scotland. For some, the pace of change has been too much. Neil Lennon arrived at a moment in time and became the sum of all their fears and insecurities. This is not to excuse or justify, merely to offer an explanation.

In the 1955 film Bad Day at Black Rock, Spencer Tracy goes looking for justice in a small American town with a secret. Eventually, he finds it and the town finds redemption. Political, cultural and civic Scotland has yet to explain its failure to protect Neil Lennon. Until it does so, it can never fully be redeemed.