The death of nine American soldiers in a helicopter crash Tuesday in southern Afghanistan has made 2010 the deadliest year yet for the US-led occupation forces.

The International Security Assistance Force (ISAF), the NATO umbrella for the occupation of Afghanistan, issued a statement declaring, “The cause of the crash is under investigation.” It added, “There are no reports of enemy fire in the area.”

A spokesman for the Taliban, Yousuf Ahmadi, however, claimed that its fighters had brought the helicopter down.

The crash took place in the Diachopan district of Zabul province, according to Muhammad Jan Rasoolyar, a spokesman for the provincial governor. Zabul borders Kandahar province, the center of an ongoing US military offensive, to the west and Pakistan to the south. It has long been a center of resistance to foreign occupation.

While the ISAF withheld the nationalities of the troops pending notification of their families, officials speaking on condition of anonymity reported that all of the dead were Americans.

The deaths bring to 530 the number of US, NATO and other occupation troops killed since the beginning of this year, according to the web site icasualties.org, which tracks casualty reports. With more than three months of the year left to go, this already surpasses the 517 fatalities in 2009.

The death toll for US troops had already surged past the total 2009 figure by the end of last month. Thus far, 351 US troops have died in Afghanistan this year, compared to 317 for all of 2009.

The latest casualties bring to 2,098 the number of American and other foreign occupation troops killed in Afghanistan since the US invasion of the country in October 2001.

Tuesday’s helicopter crash was the deadliest for the US military since May 2006, when ten American soldiers were killed in a helicopter crash during combat operations at a mountaintop landing zone in eastern Kunar province.

Helicopter crashes, resulting in some cases from mechanical failure and in others from hostile fire from the Afghan resistance, have been a recurrent cause of casualties in Afghanistan. The US-led occupation forces rely heavily on the aircraft for movement, given the inability to establish reliable control over the country’s roadways, where military convoys are subject to attack.

Ground fire from armed fighters resisting the occupation brought down a Canadian helicopter in Kandahar province last month, injuring eight soldiers. Last June, a copter was brought down by hostile fire in Helmand province, killing four Western occupation troops. In the deadliest such incident, 16 US soldiers were killed when a Taliban rocket struck a Chinook transport helicopter in Kunar province in June 2005.

The latest spike in casualties has occurred as all of the 30,000 US troops that the Obama administration ordered to Afghanistan as part of its “surge” are on the ground, bringing the total occupation force to nearly 150,000, with American troops making up two thirds of that total.

Many of the additional 30,000 US troops have been massed in Kandahar, the southern Afghanistan province which is considered a Taliban stronghold. The occupation forces have been carrying out “clear and hold” operations in the Argandhab Valley, a key entry-way into the city, and in the neighboring farming districts of Zhari and Panjwayi, west of Kandahar.

Pentagon officials and the military’s uniformed brass are attempting to diminish expectations as to the strategic impact of the new offensive. In part, this is driven by the failure of its last offensive, carried out earlier this year in Helmand province’s Marjah district, to quell Afghan resistance or bring stability to the area. The Pentagon had touted the operation as a key turning point in the war.

More fundamentally, however, the military is anxious to dispel any illusions that Washington will make good on the pledge made last December by President Barack Obama to begin withdrawing US troops from Afghanistan in July 2011.

Officials quoted by the Wall Street Journal Tuesday dismissed any expectation that a strategy review that the Obama administration is set to carry out in December will produce any significant change in US operations in Afghanistan.

“Frankly, the way the situation is today, you are not going to see a big difference by December,” a senior US military official told the Journal.

“Obama administration officials are themselves lowering expectations for the December review, saying the evaluation will likely result in fine-tuning rather than dramatic change,” the newspaper reported. “Defense officials also now say they believe the December review won’t result in significant decisions about how many troops to withdraw in the following year.”

The Journal reported that military officials are “managing expectations of the drawdown of troops in July 2011.”

“While many in the military say they believe the administration will want to see a significant number of forces begin to withdraw in July, military officials said they aren’t planning to withdraw entire battalions or brigades,” the newspaper reported. Instead, it continued, “the drawdown will focus on ‘thinning out’ front-line troops, sending home small company-size units.”

Officials told the Journal that if the US military is able to hand over control of some of the less embattled regions of the country to Afghan security forces, American troops there will be redeployed to the strongholds of the resistance in the south and east of the country.

“We want to reinvest transition dividends to improve security,” one senior official told the Journal. “We can take some of those resources, instead of sending them home, you reinvest them in Kandahar, you up-gun where you still have issues.”

Along similar lines, Brig. Gen. Frederick “Ben” Hodges, the deputy coalition commander in southern Afghanistan, stressed to the Washington Post that the Obama administration’s supposed deadline for beginning a troop withdrawal could not be allowed to interfere with assuring Afghans that the US occupation will continue indefinitely. “When they are confident we’re staying, then they’ll help,” he told the Post. “But if they’re not sure, then they will sit on their hands.”

The Pentagon’s own American Forces Press Service quoted an Army colonel commanding US forces in the north of the country as telling Pentagon reporters via a video news conference from Afghanistan that “Troop numbers there will remain at the current level, with no expectation for a mission change or withdrawal in the near future.”

Col. Sean Mulholland, deputy commander of Regional Command North, was quoted as describing Obama’s July 2011 deadline as merely “the date in which leaders and policy makers will begin to discuss transition.”

“I don’t see any kind of drastic drawdowns forthcoming in the next few years,” Mulholland said. “It’s going to have to be a timed, phased withdrawal, obviously taking security into account.”

What these statements make clear is that the military has determined that the Afghanistan occupation must go on for years to come. Just as it rubber-stamped the generals’ demand for a 30,000-troop surge, the Obama administration is prepared to continue the US war indefinitely, with the inevitable result of thousands more US troops and tens of thousands of Afghan civilians killed and wounded.

The July 2011 deadline announced by Obama at the end of last year has already been exposed as mere window-dressing for the administration’s sustained military escalation, designed to temporarily divert the overwhelming popular opposition to the war within the US itself.