This week he returned to South Carolina's Lowcountry, where much of the 1994 film was shot, for the second annual Lt. Dan Weekend, a gathering of military personnel and vets who were severely wounded in Afghanistan and Iraq.
Volunteers raise donations so the vets have a chance to get away. Sinise's Lt. Dan Band scheduled a benefit concert on the Beaufort waterfront Friday night.
"We have a lot of folks who are banged up out there and need our help," said Sinise, the star of "CSI-New York," during a Thursday reception for the 65 wounded personnel, their caregivers and families attending the four-day weekend. "I always remember this great Calvin Coolidge quote that the nation that forgets its heroes will itself be forgotten."
The cover band, formed in 2004, plays about 40 shows a year, most of them for charity and many for military personnel and veterans. Sinise has also formed a foundation to support the military and first responders.
The idea of the Lt. Dan Weekend came from Steve "Luker" Danyluk, who in 2007 founded the Independence Fund which provides support for those who suffered severe wounds in the war on terror.
Danyluk, who moved to the Beaufort area two years ago, is a Marine vet who served in Iraq and later worked with the wounded at the Military Severely Injured Center. He said he was sitting in a restaurant with his wife and saw pictures from "Forrest Gump" on the wall.
"It just popped into my head that we should get Gary Sinise here to do a benefit because he had performed for us in Dallas," he said, adding that he e-mailed Sinise. "I didn't know if I would get anything back but I got a response in about 20 minutes."
Sinise replied "Lt. Dan Band in Beaufort - make it happen," he recalled.
This weekend's events include the concert, a bike ride, golf tournament, an art exhibit dealing with the wars and films, including a presentation of "Happy New Year," about injured veterans dealing with the psychological scars of combat.
More than $1.5 million has been raised through the two Lt. Dan weekends.
"It's a purely volunteer effort. We don't have any big corporate sponsors although American Airlines ran a flight to bring in the band," Danyluk said. "Gary has donated everything."
Judy Ferguson, a 69-year-old retiree from Bluffton who was helping with the reception, said the wounded warriors bring home what the military has been dealing with for a decade.
"When you see them, you have no doubt in your mind of what these guys are facing," she said.
One of the wounded is 22-year-old Marine Cpl. Justin Gaertner, who lost his lower legs to an IED, or improvised explosive device, in Afghanistan. He was working with a unit sweeping mines.
He said he has been walking on artificial legs for about six months now and has gone water skiing, scuba diving, kayaking, fishing and sky diving.
"It's all about who you are. If you are self-motivated and want to go out and do that stuff you can," he said.
But he's not sure he now wants to stay in the Marines.
"Unless they give me my metal detector back, I don't want to stay in," he said. "I'm not the kind of guy to sit behind a desk."
Danyluk said it's sometimes hard for people to deal with the severely injured.
"It's really painful to look at somebody who has a severe injury and you can't help think, `What if it was me,"' he said.
"Not everybody wants to go to a hospital and visit wounded soldiers," Sinise agreed. "As many as the dozens and dozens of times I have visited the hospital, there is always a little bit of apprehension because you don't know what you're going to see."
But as you get there, he said, "You forget about yourself and put yourself in their shoes and they are happy to see you."
On the Web:
Lieutenant Dan Weekend: http://www.ltdanweekend.com/
Independence Fund: http://www.independencefund.org/
Gary Sinise Foundation: http://www.garysinisefoundation.org