The Pentagon will now allow women in the US military to fight in direct combat on the front lines, but is this decision actually centuries in the making? The Post’s Dana Priest explains what this watershed moment means for military and American culture. (The Fold/The Washington Post)

Hours after the Pentagon lifted the ban on women in combat, Valerie Warner typed out an ­e-mail to her grandfather, Volney Warner, a retired four-star general who helped oversee the integration of women into the Army in the 1970s.

Valerie Warner, an Iraq combat veteran, excitedly laid out her ­detailed plan for incorporating women into infantry units.

A few hours later, her grandfather replied, writing, “I remain convinced that women are better at giving life than taking it.” He added that although women play an important role in the Army, he thinks that they have no place in combat units.

No family better captures the flurry of debate triggered by Defense Secretary Leon E. Panetta’s historic announcement this week than the Warners. The decision alters decades of military tradition and opens new opportunities for women and a new debate on their role in the military.

Four of Warner’s eight grandchildren — two of them women — have fought in the Iraq and Afghan wars. In 2005, one of his granddaughters, 1st Lt. Laura M. Walker, was leading her engineer unit in Afghanistan when a roadside bomb detonated beneath her vehicle and killed her. The 24-year-old was the first female U.S. Military Academy graduate to die in combat in Iraq or Afghanistan.

Their family story shows the progress made by women in the military in the past decade. But it also highlights the significant ground women must still cover to win acceptance in the military’s last all-male bastions.

As a general commanding the 9th Infantry Division in the 1970s, Warner oversaw the integration of women into hundreds of non-combat arms-support jobs. “There was little time to prepare,” he said. “They just started to arrive.”

Soon, he found himself officiating disputes over whether hair should be tucked under steel helmets and how to handle crying female soldiers.

After a few months, he decided that his initial doubts about the women were misplaced. “Their job performance was what surprised me,” he said. “The first group of women were better than the men. They really wanted to be there and knew they were part of an advanced guard.”

Decades later, as a grandfather, he suggested that all of his grandchildren consider a career in the Army. “I encouraged them to take on something more important than themselves and told them the military is a good place to do it,” he said in an interview Thursday.

Two granddaughters, Laura and Valerie, took his advice. They were smart, athletic and eager to prove that they were just as capable as their male counterparts. While Laura was at West Point, Valerie attended George Mason University and enrolled in ROTC.

Before the two deployed in 2004 — Laura to Afghanistan and Valerie to Iraq — Warner offered them the same advice: “Follow in the tracks of those ahead of you. . . . Keep a round in the chamber. Take care of your soldiers. Do not try to be a hero.”

These days, a painting of Walker in her uniform hangs in the hallway of his home in McLean. Warner, 86, calls her death a “personal tragedy” but insists that his opposition to women in combat jobs is driven by his experiences in fighting wars, not the loss of his granddaughter.

When he was a lieutenant in Korea in the 1950s, he and his men spent months in the bitter cold and endured killing on a scale far greater than the losses faced by U.S. troops in Iraq or Afghanistan over the past decade. Under such conditions, he said, he is concerned that male soldiers would be more likely to worry about the safety of female soldiers. A gender-integrated infantry company, he said, would become “a less effective killing machine.”

A decade of combat has chipped away at the support for Warner’s stance inside the military. In Iraq and Afghanistan, female soldiers have operated heavy machine guns on Army trucks in combat and inflicted casualties on the enemy. They have led patrols to clear roads of buried bombs, one of the most dangerous missions in the military.

“I love my granddaughters dearly, and they both totally disagree with me,” Warner said.

Valerie Warner, who left active duty as a first lieutenant in 2006 after her Iraq deployment, acknowledged that today’s Army has not experienced the death and privation that her grandfather and his soldiers endured. “I cannot fathom what it was like in World War II or Korea,” she said.

And she conceded that integrating female soldiers into front-line combat units will probably be more complicated than lifting the ban on openly gay troops, who are already serving effectively alongside their straight counterparts.

Her solution, which she outlined in the e-mail to her grandfather, was for the Army to move slowly and ensure that the first group of female soldiers assigned to combat units has been tested in battle in Iraq or Afghanistan. “I believe you want women who have actually been in a combat support role and who have fired a .50 [caliber machine gun] or been on dismounted operations to be the ground breakers here,” she wrote.

As a young officer, Valerie said, she wanted badly to be part of an infantry unit, a position closed to women at the time. She said her biggest regret is that the decision to lift the ban came too late. “I wish this could have happened 12 years ago,” when she was still in college, she said.

The 32-year-old said she loved walking long patrols, land navigation and firing weapons. “It’s the fun stuff,” she said.

She also had another reason for wanting to be an infantry soldier. She wanted to be like her grandfather. “He is the best man I know — and no one has ever really measured up to him and never will in my eyes,” she said in an interview.