Bulger boasted of his friendships with the big hitters and the hitmen from the oul' country. And associates said he loved having a political cause to cover up his ruthless Mafia killings, extortions and racketeering.
But mobster Bulger, who led the notorious Winter Hill criminal gang in Boston, did more than wipe away a tear at hearing the emotion of Four Green Fields, or sound off after listening to the fighting talk of the Boys Of The Old Brigade.
Bulger bragged about raising millions of dollars for the IRA and then went one step further by actually helping to arm the terrorists he admired so much. From a distance.
And he was prepared to kill in his pursuit of Irish freedom – even though he targeted the wrong man.
Earlier this week Bulger, who was once the FBI's second most-wanted man (after Osama bin Laden) was convicted in Courtroom 11 at the Joe Moakley Federal Courthouse in Boston of 11 murders and a string of other underworld charges.
Bulger, who is now 83, had been on the run for 16 years, until he was arrested in 2011 with his long-term partner, Catherine Greig.
The couple had been likened to an elderly Bonnie and Clyde, but had, in fact, been living a quiet, though well-heeled, life in Santa Monica, California.
One of Bulger's murder convictions was for the brutal torture and murder of Irish- American fisherman – and IRA supporter – John McIntyre, who was one of the main players in the Marita Ann gun-running plot to the Provisionals.
McIntyre had sailed a fishing trawler, the Valhalla, with a $1m (£50,000) cargo of 160 guns, grenades and 71,000 bullets from Gloucester, near Boston, to rendezvous with five top IRA members, including the current Sinn Fein TD Martin Ferris, on a ship called the Marita Ann off the Kerry coast in September 1984. But Irish navy gunships were waiting for them.
It's been claimed the arms smuggling operation was set up by ex-IRA leader Joe Cahill, who met Bulger several times.
McIntyre's body was found in a shallow grave in Boston in January 2000 and, shortly afterwards, I went to America to compile a TV documentary about him.
And it was no time at all before the name of Whitey Bulger came up, as I talked to McIntyre's family, to lawyers and to the FBI. McIntyre's brother, Chris, and mother, Emily, told me Bulger murdered John after the IRA and the Mob – an unlikely partnership, if ever there was one – looked for a fall guy for the tip-off which led to the seizure of the Marita Ann. The British and Irish authorities had dropped broad hints that the mole was in America and McIntyre quickly came under suspicion.
But he wasn't to blame.
The man who gave the information about the Marita Ann was former IRA leader and police informer Sean O'Callaghan, who, during an interview with me for the documentary, made no secret of what he'd done.
By a bizarre twist, however, John McIntyre did become a tout after the event. He was arrested after a burglary and cut a deal by giving information about the Marita Ann's American conspirators and about another boat, which was laden down with Bulger's drugs.
Chris McIntyre told me: "[John] gave up Whitey Bulger that night. He gave up the Winter Hill crew. And remember: they could have had you killed anytime, anywhere. Once you crossed Bulger, you could count your time left on the calendar."
But Chris McIntyre added: "I'm not sorry that he did what he did to Whitey Bulger. It would be like me saying I was sorry for spitting at Satan."
Before John McIntyre could flee the States, he was lured to a house party. One of Bulger's former allies, Kevin Weeks, gave a chilling testimony in court about what happened next.
He said McIntyre was chained to a chair and interrogated by Bulger, who had a sub-machine-gun.
Weeks said that, when McIntyre confessed, Bulger tried to strangle him with a rope, but it was too thick and Bulger shot him instead, before one of his henchmen pulled out McIntyre's teeth to make any future identification of his body impossible.
Throughout the trial, there were disputed claims that Bulger was himself an informer.
However, it did emerge that he left Boston after an FBI man told him he was about to be arrested.
In 2000, the then-director of the FBI in Boston, Barry Mawn, denied that they'd only been half-hearted in their search for Bulger.
"That is definitely not the case," he told me. "I have designated a task force that are devoted full time to tracking him."
As for Martin Ferris, he said: "I don't know Whitey Bulger. I never met him. I never had anything to do with him.
"You can get the transcripts of the trial and look at them. There's nothing about him."
Bulger will be sentenced in November. But, in spite of the wishes of John McIntyre's family, he won't face the death penalty – though even he accepts that he will die behind bars.