Oliver Warnock, 72, a seriously ill, Irish-born decorated US army veteran, has one wish as he battles a spreading cancer -- that his two sons in Ireland become eligible to live with him in the US as his final fight unfolds.

However, immigration have so far refused to allow his sons to join him, according to Tampabay.com, the online edition of the St. Petersburgh Times.

Now this July 4th as he battles prostate cancer that has spread to his lymph nodes, he is making one more major effort. The cancer, linked to Agent Orange, was first diagnosed in 2004 and has now returned and the diagnosis is grim.

In 1963, Oliver Warnock. then a bus driver, left Dublin for the U.S. in aboard a ship called the S.S. America. After arriving in New York, he worked two jobs including as a bartender. A few years, later he was drafted to go to Vietnam. His wife and family joined him for a time but when he was drafted, knowing no one, they returned to Ireland. The couple eventually divorced in 1975, but he stayed close to his sons.

On May 5, 1968, Warnock performed heroically on a Vietnamese battlefield as a U.S. tank commander involved in an eight hour battle. His silver star citation noted "Warnock continuously exposed himself to ... fire to engage enemy bunkers with the externally mounted 50-caliber machine gun" single-handedly taking out several bunkers and killing nine enemy troops, a report of the engagement said.

He was hit by shrapnel in the back and stomach. He was awarded the silver star, the nation’s third highest honor, and given automatic citizenship four months later.

After three years of combat, he won two Purple Hearts, five bronze stars, including two for valor, and the silver star, the nation's third-highest combat decoration.

His commendations include terms such as "extraordinary courage" and "exemplary devotion to duty.”

Now his wish is to have two of his sons join him but because of immigration regulations that have proven very difficult.

After six years of trying every possible route his sons have not been approved for residency.

"This just upsets me so much," he said. "It's so frustrating."

Warnock claims that bad advice from bureaucrats he dealt with has prevented his sons joining him.

"Now I'll be dead before they get permission to come here," he says

One son, Peter Warnock, 43 an actor who does voice-over work, stated he wanted to join his Dad as soon as possible.

"I think it's pretty obvious, if your father is a man with the record my father has, all this should all be a piece of cake to sort out," Warnock said.

Warnock is now pleading with politicians to help him sort it out.

"I wouldn't give up this country for anything," Oliver Warnock said. "I've never come across a country as wonderful as the United States. It's done everything for me."

Except allowing his kids to join him in his last battle.