The Taliban have made the best of their lack of artillery shells for roadside bombs. These shells were the most frequently used source of explosives in Iraq. Saddam's stockpiles of old ammo are not available in Afghanistan, so the Taliban use homemade explosives, based on fertilizer. The Taliban have found that if they place these bombs in non metal containers, the American metal detection devices can't find them. But there are many other ways to detect the bombs.
Last year, the Taliban employed 8,159 of these bombs, compared to 3,867 in 2008 and 2,677 in 2007. The peak year of use in Iraq was 2007, when 23,000 were employed. In both countries, most of the bombs are detected and destroyed before they could hurt anyone. In Iraq, the Sunni Arab terrorists (al Qaeda and Saddam loyalists) never fully accepted the fact that the bombs, by killing more Iraqis than foreign soldiers, turned the population against them. That was a major reason for the defeat of the Iraqi terrorists after 2007. The same pattern is playing out in Afghanistan, and the Islamic terrorists still can't come to accept the truth.
In response to the fertilizer bomb threat (which mostly killed Afghan civilians), the Afghan government banned the use of ammonium nitrate fertilizer in January. Some 90 percent of the roadside bombs use ammonium nitrate. Farmers were given 30 days to sell their ammonium nitrate to the government, or have it seized without compensation. The government has, for years, been urging farmers to stop, for environmental reasons, using ammonium nitrate. But farmers don't like urea based fertilizers, which are now the only kind they can legally use.
The terrorists can still smuggle ammonium nitrate in from Pakistan, but the government can probably make it difficult to sneak ammonium nitrate in via truck. Bringing the fertilizer in over the mountain trails on mules is more expensive. But the Taliban can afford to pay, because of their links to the drug gangs. Both groups want foreign troops out of the country, so heroin can be produced and smuggled without interference.
In Afghanistan, IEDs (Improvised Explosive Device, a roadside, or suicide car bomb) now cause over 70 percent of NATO casualties. Ammonium nitrate is a powdered fertilizer that, when mixed with diesel or fuel oil, can be exploded with a detonator. While only about 40 percent the power of the same weight of TNT, these fertilizer bombs are effective as roadside bombs. But they are bulkier and a slurry. Moreover, the fuel oil must be mixed thoroughly and in exactly the right proportion, otherwise the explosive effect is much less than expected. But the biggest problem is that if you can't get the ammonium nitrate, you have no explosives.
For the past year, even before the ban, U.S. and NATO forces have been searching for ammonium nitrate. Even the supplies held by farmers were being taken. But the troops were paying twice what the farmers paid for it. Thus many farmers are voluntarily turning their ammonium nitrate (usually in 50 kg/110 pound bags) in for the instant profit. Other, non-explosive, fertilizers were made available to the farmers, at equivalent cost to ammonium nitrate. Imports of ammonium nitrate into Afghanistan had been monitored, but the Taliban either paid high prices for the stuff, or just stole it. All this didn't make it impossible for the terrorists to get the fertilizer, but just more difficult. This effort resulted in fewer, and less powerful, bombs. The ban on ammonium nitrate will make it even more difficult to build the bombs.