WASHINGTON — Several U.S. senators are demanding that the Obama administration pressure Pakistan to cut off the supply of chemical fertilizer to Afghanistan, where it is used as the main ingredient in homemade bombs, the No. 1 killer of U.S. troops.
"We need to be focused on this," Sen. Bob Casey, a Pennsylvania Democrat who chairs a Foreign Relations committee panel on the region, said in an interview. "I have not seen the kind of urgency that we need to have."
Last week, Casey and 19 senators sent Secretary of State Hillary Rodham Clinton a letter requesting "urgent action" to stem the flow of fertilizer from Pakistan into Afghanistan. They wrote that they want Pakistan to pass a law regulating fertilizer. They also want tighter border controls to eliminate shipments into Afghanistan, where the material is illegal for farming but still used for mining and construction.
"We have each lost constituents to IEDs in Afghanistan and visit with young servicemembers injured by these terrible weapons," according to the letter.
The Pentagon, the State Department and intelligence agencies have launched Operation Bolt Cutter to deprive insurgents in Afghanistan of ammonium nitrate. When mixed with fuel, ammonium nitrate makes for a potent bomb used in nearly 85% of improvised explosive devices (IEDs).
IEDs have been particularly deadly in recent weeks against U.S. forces on foot, who have little protection from explosions. An especially large bomb, or bombs, killed eight U.S. servicemembers in one attack in southern Afghanistan on Friday. In 2010, IEDs killed 268 U.S. servicemembers and wounded 3,366 others.
Lt. Gen. Michael Barbero, who leads the Pentagon's Joint IED Defeat Organization, said in a recent interview that fertilizer was "ubiquitous" in Afghanistan. Bolt Cutter, he said, is an attempt to harness the effort of multiple government agencies to "have an impact on the flow and availability" of fertilizer in Afghanistan.
Specifics of the operation are classified.
The State Department has said in previous statements that two plants in Pakistan continue to make ammonium nitrate even though farmers there generally use different fertilizers. State said Pakistan also imports the chemical, exceeding domestic usage.
Casey said he has petitioned officials in Pakistan for help in addressing the problem. They have acknowledged the problem but remain mostly non-committal, he said.
"You don't often get formal responses," Casey said.