They destroyed much of the U.S. troops' heavy munitions, broke through their lines, and entered the main base before being finally repelled by artillery and aircraft.

[13] In contrast to previous assaults, from roadside bombings to haphazard ambushes, this attack was well-coordinated; fighters across different insurgent groups were able to precisely target key equipment, such as a wire-guided missile launcher, through a sustained and disciplined effort.

Lieutenant General Richard F. Natonski conducted another investigation in late 2009 which led to orders of reprimand for the chain of command.

[15] In June, a small contingent of 72 troops, 48 American and 24 Afghan, were operating in and around Wanat, a mountain Quam[clarification needed] that was the center of the Waygal District government and about 5 miles (8.0 km) from the coalition military base Camp Blessing.

"[citation needed] Five days before the battle, on July 8, a platoon from the Second Battalion, 503rd Infantry Regiment, 173rd Airborne Brigade Combat Team established Vehicle Patrol Base (VPB) Kahler and a separate observation post called OP Top Side near Wanat.

[14] Their goal was to create a Combat Outpost (COP) to connect with and provide security for the local populace, coordinate $1.4 million in reconstruction projects, and disrupt Taliban activity.

It was decided that soldier labor – with the aid of an engineer squad and a Bobcat front-end loader already at Bella – would be good enough to prepare an initial defense in the six days until heavier equipment arrived.

The number of men at the base was judged adequate to defend against intelligence estimates that placed the insurgent forces in the local area at about 150 experienced fighters, though they did not know that attackers would be backed up by other guerrilla groups from neighboring regions as far away as Pakistan and Kashmir.

[3][21] The day before the attack, militants began flowing water through an irrigation ditch feeding an unused field, creating background noise that masked the sounds of the advancing fighters.

Although the Americans believed that 100 or 200 attacked the base, a senior Afghan defense ministry official who did not reveal his name told Al Jazeera that he had information it was between 400 and 500 fighters.

Tamim Nuristani, former governor of Nuristan, believed that numerous Taliban and Pakistani militant and terrorist groups banded together from surrounding regions including Kunar and the Bajaur tribal agency in neighboring Pakistan.

According to U.S. intelligence, groups operating in the region included Taliban, al-Qaeda, Kashmir-based Lashkar-e-Taiba and Pakistan-based (as of 2013 still located in one of many strongholds in the Bajaur agency of FATA (Federally Administered Tribal Areas in Kunar and Nuristan of Afghanistan)) Hezb-i-Islami.

[4] A NATO spokesman believed that the Taliban had moved into and expelled a nearby Khel (small village-tribe subdivision) for the attack.

[3] About 4:20 a.m. on July 13, Taliban forces opened fire on the base with machine guns, rocket-propelled grenades (RPGs), and mortars.

The insurgents next destroyed the Humvee-mounted TOW missile launcher inside the combat outpost with coordinated fire from unguided RPG rockets.

Three times, teams of soldiers from the main base ran through Taliban fire to resupply the observation post and carry back the dead and wounded.

[citation needed] Two U.S. soldiers, platoon leader First Lieutenant Jonathan P. Brostrom, 24, of Hawaii and Corporal Jason Hovater, were killed trying to deliver ammunition to the observation post.

[22] AH-64 Apache attack helicopters and a Predator unmanned aircraft drone armed with Hellfire missiles arrived over the base about 30 minutes after the battle began.

[30] Civilian deaths caused by allied operations had increased sympathy among Waygal residents for the Taliban, who were allowed to move into the Quam.

The residents may have been further dismayed by the failure of the Afghan president, Hamid Karzai, to address the concerns of a delegation of elders and maliks in Kabul two days previously.

[32] The same report criticized the actions of the involved commanding officers as being counterproductive to military goals, stating that "The highly kinetic approach favored by TF Rock ... rapidly and inevitably degraded the relationships between the U.S. Army and the Waigal population.

Kilcullen stated that in March 2008, The fact that Kunar has bucked the general trend [downward trend in security across the country] seems largely to be the result of a consistent U.S. strategy of partnering with local communities to separate the insurgents from the people, bring tangible benefits of governance and development to the population, and help the population choose their own local Khan's (Protectors, usually military), through elections.

[3] Speaking at a Pentagon news conference after the attack, U.S. Chairman of the Joint Chiefs of Staff, Navy Admiral Mike Mullen said the incident indicated that "... all involved with operations on the (Pakistan-Afghanistan, especially the porous Kunar, Kashmir, and Nuristan), border must do a better job of policing the region and eliminating the extremists' safe havens in Pakistan's federally administered tribal areas that are launching pads for attacks on coalition forces.

"[41] An investigation by the U.S. Army, completed on August 13 and released to the public the first week of November 2008, found that the Taliban fighters had been assisted by the Afghan local police (ALP), forces and a district leader.

In response to the report, Schloesser concluded that the governor and local police chief "... had probably been acting under duress and had been cooperative with American troops."

Senator James Webb asked the U.S. DoD Inspector General to formally examine the battle and the U.S. Army's investigation into the event.

[22][43][44] Cubbison had written the report at the request of Lieutenant General William B. Caldwell IV, commander of the United States Army Combined Arms Center.

[46] On September 30, 2009, U.S. Central Command commander General David H. Petraeus appointed U.S. Marine Corps Lieutenant General Richard F. Natonski to lead a new inquiry into the battle and which would look into related issues "... beyond the tactical level ..."[22][47][48] A later review was conducted by General Charles C. Campbell which "... focused on the totality of circumstances that included and affected actions at Wanat," including interviews of the officers involved, and reviews of previous investigations with the exception of the Fort Leavenworth Combat Studies Institute (CSI) narrative – stating that it had "... not undergone pre-publication vetting and academic review in accordance with standing CSI research protocols.

These soldiers were well-trained, well-led, and fought bravely to defeat a determined and intense enemy action to overrun their base in Wanat.

In addition to the family members, the letter was signed by Senators Daniel Akaka, Jim Webb, Saxby Chambliss, Patty Murray, and Claire McCaskill.