by Laurent Lozano and Daphne Benoit

FORT HOOD, US - At stricken Fort Hood, President Barack Obama Tuesday shouldered the role of America's national healer, as a country rose above its deep divisions in a moment of shared mourning.

Weaving a stirring parable of national sacrifice, Obama metaphorically enshrined 13 victims of last week's massacre on this giant military base with a new generation of US war dead from Iraq and Afghanistan "who now belong to eternity."

Many in the 15,000 strong crowd of soldiers in camouflage fatigues and civilians dressed in black meanwhile quietly mourned their fallen brethren, still unable to quite believe the horror of what is believed to be the worst-ever mass shooting at a US military base.

Framed by wailing bagpipes and a mournful rendition of "Amazing Grace", Obama dwelt on the savage irony that those gunned down, allegedly by a troubled Muslim comrade, died not at war but in a supposed safe haven.

"These Americans did not die on a foreign field of battle," Obama said, as he eulogized the 12 service personnel and one civilian killed.

"They were killed here, on American soil."

"It is this fact that makes the tragedy even more painful, and even more incomprehensible."

Some observers said Obama's poetic remarks amounted to the best speech of his presidency, and the latest in a sequence of poignant oratory which helped power his stunning rise to the pinnacle of US politics.

Melding his roles as commander-in-chief and chief national mourner, Obama, who recently flew to a Delaware air base to watch fallen US soldiers return home, drew comparisons between Fort Hood victims and other young war dead.

In another poignant twist, his eulogy at Fort Hood came a day before November 11, Veterans Day, when Americans remember the fallen of current and past wars.

"I think all of us - every single American - must acknowledge that this generation has more than proved itself the equal of those who have come before," Obama said.

"We need not look to the past for greatness, because it is before our eyes."

Ministering to Americans, almost like a national pastor, is a task that periodically falls to American presidents, and the speeches US leaders make at moments of national grieving are often remembered as their greatest rhetoric.

In the wake of a tragedy, some leaders see a spur to renew national purpose and an affirmation of what they view as American ideals.

In 1986, President Ronald Reagan soothed his country's shock when he remembered seven crew members killed in the space shuttle Challenger disaster who he said had "slipped the surly bonds of Earth to touch the face of God."

In 1995, President Bill Clinton, who was in deep political trouble at the time, gave voice to the grief of his nation after the bombing of a federal building in Oklahoma City in an act of domestic terror.

In 2001, President George W. Bush infused new steel into his traumatized countrymen with his rallying cry from the rubble of the World Trade Center in New York after the September 11 attacks.

Some mourners at the Fort Hood ceremony seemed to appreciate Obama's words.

Sergeant Perry Osburn, 30, from New Roades, Louisiana, has served three tours in Iraq, and came with his wife Megan and young daughters.

"It's a big deal," he said, of Obama's decision to delay a planned trip to Asia by one day to attend Tuesday's ceremony here.

The Republican governor of Texas, Rick Perry, called the Democratic president's address "spot on".

Lieutenant Colonel Tommy Eberhart, deputy director of human resources at Fort Hood, who witnessed the carnage allegedly unleashed by gunman Major Nidal Hasan at the base last week, also praised Obama for coming.

"It means everything to the people that work here. It's the president of the United States."

But for specialist Peter Kniskern, who returned home from Iraq in July, the day was not about Obama, but his fallen comrades.

"It's not really about the president, one of our guys that we trusted went in and killed other soldiers and we are here to pay respect to them.

"It's brother and sisters."

Sergeant John Vaccaro, of the US 38th Cavalry meanwhile marvelled "it was supposed to be a safe spot." --AFP