With a grandfather who flew bi-planes in World War I and a great uncle who was a prisoner of war for three-and-a-half years under the Japanese during World War II, Barnett has a deep interest in military history.

It was on that day 17 years ago that his life was irrevocably changed, that Tasmania's now Veterans' Affairs Minister joined Garry Ivory in his seemingly endless quest to see the late Teddy Sheean recognised with a Victoria Cross of Australia.

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"The Teddy Sheean story resonated with me from day one, thanks to Garry Ivory's advocacy on behalf of the family," Barnett says. "And clearly things were amiss."

Fast forward 16 years to 2019: Barnett, no longer a senator but a Cabinet minister in Premier Peter Gutwein's government, is reading the submissions to a Defence Honours and Awards Appeals Tribunal inquiry into whether or not Ordinary Seaman Sheean should receive a VC.

The politician's eyes well up with tears as he realises the evidence attesting to Sheean's gallantry is overwhelming.

"I knew the evidence and the facts were so powerful that we could get the VC for Teddy," Barnett says. "So that's when I was first overwhelmed with joy."

Since that fateful day 17 years ago when he met Ivory, Barnett has in numerous forums prosecuted the case for Sheean to receive a VC.

It began in Canberra, where he started asking questions of the then federal defence minister Robert Hill, and of the bureaucracy via Senate estimates.

In 2011 came the tribunal's valour inquiry, which two years later concluded that a VC for Sheean was not warranted.

"Even thinking about it now, it makes me so disappointed and angry that they delivered that result," Barnett says.

Six years later, a second inquiry was held after Barnett appealed Chief of Navy Mike Noonan's decision not to hold one. It ultimately found that Sheean should be recommended for the high honour.

The federal government had other ideas, though, ignoring the tribunal's advice. For Barnett and Ivory, this was deeply upsetting.

And so begun the last chapter in the dogged pair's fight.

Prime Minister Scott Morrison established an expert panel, chaired by former federal opposition leader and ex-Australian War Memorial director Brendan Nelson, to review the Sheean case.

Two weeks ago, Morrison announced that Sheean would be recommended for a VC, which Queen Elizabeth II approved.

Scenes of jubilation erupted at the Launceston RSL, where Barnett and Ivory raised a toast to the war hero whose acts of courage have inspired them for so many years.

Recognising the 75th anniversary of the end of WWII:

It was a long time coming and Barnett says that while his family "never got tired" of his Sheean obsession and always supported him it was a different story with some of his parliamentary colleagues.

"I think some of [them] were thinking that Guy keeps banging this drum and when will he ever give up," he says. "So I think they probably got a little frustrated from time to time."

While he admits there were plenty of disheartening "knock-backs" along the way, Barnett says the success of his nearly two-decades-long effort shows why one should never give up on something they truly believe in.

"I think perseverance is the key if you believe in something and you're passionate and you know it to be true," he says. "I think it's a key ingredient for success."

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