Questions on Afghan strategy touch nerve in Pentagon

* Gates frustrated about negativity

* Sensitivity reflects concerns about public sentiment

WASHINGTON, June 15 (Reuters) - Downbeat news reports and second-guessing in Congress about the course of the war in Afghanistan have touched a nerve in the Pentagon, where some worry the negativity is undercutting public sentiment before President Barack Obama’s strategy even has a chance to work.

Defense Secretary Robert Gates is among those to privately voice concerns about a wave of pessimism that they believe stems partly from embedding journalists solely with military units in Afghanistan’s south, where fighting is fiercest. Some officials talk of changes to make embeds go elsewhere too.

The Pentagon’s growing sensitivities put a spotlight on what some see as increasingly shaky support for a six-month-old war strategy that hinges on surging U.S. forces into the restive south, heartland of the Taliban, before starting a gradual withdrawal in July 2011, conditions permitting.

Asked in a Senate hearing on Tuesday whether he still supported beginning a withdrawal in July 2011 given recent setbacks in the south, General David Petraeus, who oversees the Afghan war as head of U.S. Central Command, said: “I support the policy of the president.”

But he added: “In a perfect world ... we have to be very careful with timelines.”

The Pentagon’s publicly stated goal is to be able to demonstrate at least some measure of progress across the country by year-end, when Obama’s White House will review the war effort.

But some top military officials say they won’t really know whether the counterinsurgency strategy is working or not until next summer, around the time Obama hopes to begin a draw down.

“It’s a war. It’s not a political campaign,” one military official said. “The negativity (in the press and in Congress) can go too far. There are parts of Afghanistan that aren’t going well. It’s a mixed bag.”

Gates let his frustrations show last week after a meeting with NATO ministers in Brussels.

“I, frankly, get a little impatient with some of the coverage because of the lack of historical context,” he told reporters, noting that the 30,000-troop surge ordered by Obama in December was only now beginning to be felt on the ground.

“So as far as I’m concerned, this endeavor began in full, and reasonably resourced, only a few months ago,” he said.

Gates appeared to be referring to news accounts about stronger-than-expected Taliban resistance in the southern district of Marjah and a slower start to a long-awaited offensive in the Taliban’s birthplace of Kandahar.

At Tuesday’s congressional hearing, senior lawmakers voiced strong concern about the direction of Obama’s war effort, a message that took some at the Pentagon by surprise.

“While I understand the fact that there have been developments, such as the increase in casualties, that would cause concern, there also needs to be a recognition that we know and warned this fight was going to get harder before it got easier,” said Pentagon press secretary Geoff Morrell.

Reporters typically want to embed in the southern Afghan provinces of Helmand and Kandahar, where the insurgency is strongest. But Morrell said that offered a skewed, and largely negative picture of the overall war effort.

“While Helmand and Kandahar are important provinces, they do not comprise the entirety of Afghanistan,” Morrell said. “There are many places where security is improving and life is getting better.

“So I think there are some of us, in light of that, who would like to figure out a way to provide reporters a broader view of the situation in country.”

One option being discussed within the Pentagon would be to require reporters who go to the south to also embed with military units in northern and western Afghanistan, where the security situation is far more stable.

At least one third of the new forces pledged have arrived in Afghanistan as part of the war strategy spearheaded by General Stanley McChrystal, the top U.S. and NATO commander in Afghanistan. But many of them have yet to be fully deployed.

“We do expect, by the end of the year, we’ll be able to show that they are making progress,” Morrell said. “Let’s at least allow them the next six months to prove that General McChrystal’s strategy will work.” (Additional reporting by Phil Stewart; editing by Chris Wilson)