WASHINGTON: Billions of dollars’ worth of American-supplied weapons and equipment left behind during the 2021 withdrawal from Afghanistan now serve as the core of the Taliban’s security apparatus, a US watchdog has said in its final report.
Assessments by UN monitoring bodies and a Washington Post investigation also suggest that this weaponry has already reached the banned Tehreek-i-Taliban Pakistan (TTP), further empowering a group linked to a surge in attacks within Pakistan.
The 137-page report released this week by the Special Inspector General for Afghanistan Reconstruction (SIGAR) elaborates on the scale of the American project to rebuild Afghanistan.
It added that Congress provided roughly $144.7 billion between 2002 and 2021 to reconstruct the war-hit nation and support a democratic transition.
Recent UN assessments highlight the growing regional fallout from the failed oversight of abandoned weapons in Afghanistan.
A UN monitoring panel has reported that the Afghan Taliban continue to provide the TTP with logistical and operational support, while a Washington Post investigation has revealed that dozens of US-origin weapons are now appearing in Pakistan, used by terrorists targeting the state.
SIGAR links this spillover in part to the abrupt loss of oversight following the Taliban takeover.
“Due to the Taliban takeover, SIGAR was unable to inspect any of the equipment provided to, or facilities constructed for, the Afghan National Defence and Security Forces (ANDSF) following the Afghan government’s collapse,” the report notes.
The US Department of Defence has meanwhile confirmed that roughly $7.1 billion in American-supplied equipment was left behind—ranging from thousands of vehicles and hundreds of thousands of small arms to night-vision devices and more than 160 aircraft.
The Washington Post reports that serial numbers from at least 63 weapons seized in Pakistan match those originally supplied by the United States to Afghan security forces.
Pakistani officials told the newspaper that some of these rifles and carbines are “significantly superior” to the weapons typically used by TTP fighters before 2021.
UN monitoring teams have raised similar alarms. The 36th Monitoring Report (2025) estimates that the TTP maintains roughly 6,000 fighters dispersed across Ghazni, Helmand, Kandahar, Kunar, Uruzgan, and Zabul provinces in Afghanistan, where the group is believed to share training facilities with Al Qaeda.
Speaking before the UN Security Council, Denmark’s deputy permanent representative Sandra Jensen Landi noted that the TTP continues to receive “logistical and substantial support from the de facto authorities” in Kabul.
Earlier UN assessments have documented Afghan Taliban guesthouses, weapons permits, movement authorisations, and protection for TTP leaders—arrangements that have enabled the group to deepen its presence across Afghan territory.
SIGAR’s own 2025 quarterly reports also describe a series of cross-border attacks, including an assault in South Waziristan that left 16 Pakistani security personnel dead.
The human toll of the war was far heavier. Tens of thousands of Afghans and more than 2,450 US service members lost their lives, only for the Taliban to return to power—now reinforced by the very equipment the United States spent years supplying to their former allies, the report notes.
Despite the collapse of the Afghan government, the United States has remained the country’s largest donor, providing more than $3.83 billion in humanitarian and development assistance since August 2021.
This continued support underscores Washington’s ongoing struggle to balance humanitarian responsibilities with deepening security concerns.
As SIGAR concludes its mandate after nearly twenty years, its final report delivers a stark warning. The Afghanistan mission, it argues, should stand as a cautionary lesson for any future attempt to rebuild fragile states at scale—a failure whose repercussions are now reshaping the security dynamics of the wider region.
