Jay Hamerslag stood ramrod straight on the deck of the USS Hudson, moored off Iwo Jima, one February morning in 1945. Peering through his binoculars, he observed a detachment of Marines raise an American flag atop the island's Mount Surabachi. The great battle had just ended. Hamerslag, then a 22-year-old Navy lieutenant, had played his part.

The photo of that Iwo Jima flag raising is perhaps the most indelible image of World War II. But for Hamerslag, who passed away in Rancho Mirage June 23 at age 80, wartime heroism never meant as much as the simple joys of family life.

"He imbued our house with happiness," remembers his daughter Nancy Parker of Orinda. "We laughed all the time. He believed in making the most of every minute on earth."

Jay Platt Hamerslag Jr. was a second generation San Franciscan, the son of a box factory owner who survived the great fire of 1906. He grew up attending Congregation Emanu-El and later enrolled in U.C. Berkeley, where he earned a business degree and inherited a lifelong passion for Cal Bears sports.

After the war, Hamerslag returned home, finding work in materials handling, a field he learned aboard ship. From his San Francisco apartment, he launched Hamerslag Equipment, a forklift and materials handling company. As the business grew, he moved to Burlingame.

Along the way, a friend set up Hamerslag on a blind date with Minnette Hochfeld, who, apparently, was not altogether impressed at first. But he persisted, and in 1948 the two were married. Eventually settling in the Menlo Park area, the couple had three children.

Professionally, Hamerslag was at the top of his game from day one. His company was highly successful, and Hamerslag became a pillar of the local business community. He served as president of the Peninsula Manufacturer's Association and MHEDA, a trade organization. Fifteen years ago, Hamerslag sold the business after giving it 40 years and retired to Rancho Mirage near Palm Springs.

In the Bay Area, Hamerslag dedicated himself to helping his community. He was a founder of Congregation Beth Am in Los Altos Hills and served on its original board of directors. He also served as South Peninsula chair of the Jewish Community Federation and was a past president of the Northern California region, American Technion Society.

A diabetic, Hamerslag co-founded the S.F. Diabetes Club and the Desert Diabetes Club at Eisenhower Hospital in Rancho Mirage.

Says Parker of her father's activism in diabetes treatment, "His attitude was so positive. He once said diabetes was the luckiest thing that happened to him because it made him realize he needed to take better care of himself."

And he did. Though he put in long hours at building his business, Hamerslag was an avid golfer and a rabid Giants fan. Together with Minnette, he was always on the go.

"My daughter used to visit them," notes Parker of her parents, "and she always came home exhausted, because they were always so busy."

Most important to Hamerslag was his family. Sunday was family day at the Hamerslag home, and the whole clan took regular vacations together, even when money was tight. "He'd say, 'We can't afford not to,'" recalls Parker. "He made a priority of doing things together so we would have wonderful memories."

Parker also remembers how her father would plan "dates" with each of his children. "He would take me to town, buy me a corsage and had me wear gloves," she says. "He really was a gentleman of the old school. But 99 percent of the time we went to a Giants game."

No. 1 for Hamerslag: his wife, Minnette. "Theirs was such an inspirational marriage," says Parker. "He always said his life started when he met her, and they had a ball together. Friends, travel, golf, tennis, community service. If it sounded interesting, my dad said, 'Let's do it!'"

When it came to his Jewish roots, Hamerslag set a quiet example, recalls his daughter. "Ours was a Jewish home. Dad was a huge supporter of Israel and always very generous to the Jewish community. He didn't speak a lot about it, but at his core it really defined who he was and how he felt about doing good work."

Even as age and illness began to creep up on him, Hamerslag kept a positive spirit. Earlier this year, confined to a bed and battling cancer, Hamerslag surprised his wife with a new Lexus wrapped in a ribbon and parked out front. Their love affair lasted 55 years.

Says Parker, "He was just a happiness guy."

Hamerslag is survived by wife Minnette Hamerslag of Rancho Mirage; daughters Nancy Parker of Orinda and Beth Weiss of San Mateo; son Steven Hamerslag of Rancho Santa Fe; his sister Virginia Friedman of Hillsborough, and seven grandchildren.

A memorial service will take place at 11 a.m. Thursday, July 24 at Peninsula Temple Sholom in Burlingame.

Donations may be made to the Jay Hamerslag Scholarship, c/o Bear Backers, Attn: Susie Homer, U.C. Berkeley, 2223 Fulton St., third floor, No. 4424, Berkeley, CA 94720-4424.