First in a series of reports from Afghanistan by "War Stories" host, Col. Oliver North (ret).

Camp Leatherneck, Helmand Province, Afghanistan – This Forward Operating Base, “twenty miles from nowhere” may be the fastest growing military installation in the world. In the six months since our Fox News team was last here, the base and its “population” have almost doubled in size. As one of our hosts put it shortly after we arrived, “it’s growing faster than opium poppies.” But then again, opium is one of the reasons why this place is expanding so rapidly.

If the long war here in the shadows of the Hindu Kush is going to be won – it will have to be won here in southern Afghanistan first. This forbidding terrain along the Helmand River basin is both the “spiritual heartland” of the Taliban movement and now, the primary source of opium which fuels their insurgency.

Southern Afghanistan is where the Taliban movement began – and nearly ended. Spawned with the help of Pakistan’s government in the 1980s to help defeat the Soviet occupation of Afghanistan, the faction was initially financed by oil-rich Islamists in Saudi Arabia and the Persian Gulf. By 1996 the Taliban, victors in a bloody, half-decade-long civil war had established a brutal, repressive theocracy in Kabul. Taliban leader Mullah Omar became a patron and protector of Usama bin Laden. Al Qaeda was granted near–autonomy to establish bases for indoctrinating and training “Holy Warriors.”

The 9/11 attacks changed everything for the Taliban. In less than three months a hastily-assembled, U.S.-supported coalition dubbed the “Northern Alliance” forced the Taliban out of Kabul and remnants of the regime fled south and east toward mountain redoubts and refuges in Pakistan. Kandahar, the last city in Afghanistan held by the Taliban, fell to coalition troops on the 60th Anniversary of “Pearl Harbor Day,” 2001.

Driven underground, Taliban leaders found it increasingly difficult to finance their cause. As international pressure and aggressive monetary tracking dried up much of their foreign support, insurgent leaders turned to revenues from opium to sustain their movement.

Shutting down Taliban-controlled opium poppy cultivation, processing laboratories, caches, “delivery services” and money laundering operations has become a crucial mission for the U.S.-led coalition. According to the United Nations, more than ninety percent of the world’s illicit opium, heroin and morphine base originates here in southern Afghanistan – primarily in Helmand and neighboring Kandahar provinces. Refined “product,” estimated to be worth more than $3 billion, is then moved via “ratlines” through neighboring countries to consumers in Europe, Russia, Iran and the U.S.

According to intelligence officers here, the Taliban has become a “narco-insurgency” which nets hundreds of millions of dollars from the global opium trade. Taliban networks use the money to finance the purchase of weapons and munitions and to buy protection from corrupt officials here in Afghanistan and neighboring Pakistan.

Officers in the Marine Expeditionary Brigade headquartered here at Camp Leatherneck describe the dual tasks of conducting counterinsurgency operations to protect the civilian population and interrupting this financial flow to the Taliban as “formidable” and yet “essential” to victory. To that end, these Marines and units of the newly reorganized Combined Forces Special Operations Component Command-Afghanistan are working closely with Special Agents of the Drug Enforcement Administration to target drug labs, “storage depots” and key individuals involved in the opium trade.

Last month one of the prime objectives of Operation Mushtarak in the opium-rich Marjah district of Helmand Province, was taking down local narco-networks. Though Taliban fighters pledged to repel the “foreign invaders” they proved unable to prevent NATO and Afghan government troops from reasserting control over the region.

Now, Taliban leaders are promising to prevent coalition forces from wresting control over the city of Kandahar. Over the course of the four days we have been “in-country” this time, coordinated attacks by suicide bombers have increased dramatically, causing more than fifty civilian dead and wounded. Taliban propaganda organs blame “the American and European trespassers” for the casualties. President Hamid Karzai has responded by promising to dispatch more than 1,000 additional Afghan police to the region.

Keeping this commitment is a major challenge. U.S. DEA, military and contract civilian trainers and mentors acknowledge that fielding a “qualified and capable Afghan security force” is essential to winning the fight here in “opium central.” But privately they wonder if they can train and equip adequate numbers by next summer, when the Obama administration has promised to start withdrawing American troops.

Col. Oliver North (ret) is host of “War Stories” on the Fox News Channel and a Fox News contributor.

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