The A5 is a GAA road and the proper development of it is a "human rights issue", GAA President Jarlath Burns has said.
He was speaking as families bereaved by crashes along it, got their first chance to address Belfast's Court of Appeal.
It is hearing an application by landowners challenging the commencement of works to build the £2 billion road - described as one of the most dangerous in the country.
The first phase will see the upgrade of 55km of the total 85km length of the A5 between Strabane and Ballygawley.
The A5 runs through Co Tyrone and is a vital link between Co Donegal and the main Monaghan to Dublin road.
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Speaking outside the Court of Appeal this morning, Mr Burns said it was important the association stood with the people of Tyrone.
"Getting the A5 properly upgraded is a human rights issue.
"It is a GAA road, if you want to call it that, because Tyrone's main GAA centre is on it.
"There have been so many lives lost. I think it is a responsibility on all of us to get this road upgraded."
Objectors to the upgrade of the A5 are taking legal action in an attempt to halt work on the first phase.
Since plans for the upgrade were first announced 18 years ago, 57 people have been killed in incidents along the road.
More than 3,000 acres of land on over 300 farms will be affected by the upgrade and vesting orders for the land needed for the first phase have already been issued.
The Irish Government has said it will contribute £500m, to the cost of the project.
Among those at court this morning was Angela O'Neill.
Her 72-year-old mother Kathleen McGarvey died from injuries sustained as she crossed the A5 close to Tyrone's GAA training facility seven years ago to attend mass.
Ms O'Neill said people were living in trepidation of a knock at the door to say their family was the next to be affected.
"It just devastates families. You've got my mum, who was 72, you've got younger drivers.
"You've got people from all backgrounds who are really just making their way to work, living, their regular life, like my mum. And they go out the door one minute and then they're gone."
Barrister for the A5 bereaved families Stephen Toal KC told the court how young people had been amongst those to sign a petition in support of the road.
One of them, 17-year-old Kamile Vaicikonyte, a pupil at St Ciaran's School in Ballygawley, was killed on the A5 the day after she and her schoolmates lent their names to the campaign.
"It was one of that child’s last acts on earth. In a most cruel twist of fate, she was killed on the A5 the very next day.
"Our generations have failed them miserably by not delivering this lifesaving piece of infrastructure.
"But this case, and this new road, present an opportunity for us to finally do something positive about that continuing failure."
He said parents often waited anxiously to hear their children had arrived safely at university or their work.
"No person should have to live like that ... and even more so where it is entirely preventable," he said.
And while objectors had cited loss of land and the nuisance of noise there was a noise much more difficult than that of traffic.
It was deafening silence coming from the bedroom of a dead child.
"An eternal silence that was preventable," he said.
The appeal court has heard from representatives of the landowners, Stormont's Infrastructure Department, and the bereaved families.
The court will take some time to consider the submissions before issuing its judgment.
