The surprisingly effective use of "smart bombs" in Afghanistan gave commandos a decisively powerful weapon. In the past, commandos have called in air strikes and artillery fire, but never with such accuracy. This raises the question, what about the "smart shells" for use army 155mm artillery. The reason you don't hear about the smart shells is because they cost too much. Back in the 1970s, the army began developing the Copperhead shell. This was a laser guided anti-tank shell that was supposed to cost $28,000 a round, but ended up costing over $400,000 per round. Why are smart shells more expensive? Mainly because the shell has to deal with pressures (when leaving the barrel) at up to 15,000 times normal gravity (or, in geekspeak, 15k Gs.) Getting electronics to work under those conditions is very expensive. Moreover, there isn't much room inside a 155mm shell, especially if you have to stick a guidance system in there. Originally, the army was going to buy 133,000 Copperhead shells, but as the development problems proved more formidable than expected, the number bought (beginning in 1980) fell to 3,000. The Russians later developed their own version of the Copperhead (Krasnopol), which they are selling for $40,000 a round, and it is still having performance problems. The additional problem with Copperhead and Krasnopol is that the troops in the front lines have to have the laser designator. When the Copperhead's cost spiraled out of sight, it was realized that it was cheaper to do the job with less expensive missiles. Undaunted, the army began developing the SADARM shell (eventually costing $30,000 each). SADARM was no more accurate than any other shell, but it carried three bomblets that would slowly drift to ground (after being ejected while the shell was over the target area) and use sensors to detect armored vehicles and then destroy them with a special shaped charge. It worked, it was not deemed as effective as the alternatives (missiles, or SADARM bomblets delivered in a bomb carried by an air force warplane.) Now there's another attempt at a "smart shell"; the Excalibur. This is a GPS guided shell that will hit within 20-30 feet of it's designated target. Excalibur is designed to carry smart munitions, either DPICM (with 64 bomblets) or a new SADARM (with two tank seeking bomblets). Excalibur is still in development as of 2002, and developers are trying to keep the cost down. But it's unlikely that the cost per shell will be less than $100,000. The GPS kit that turns a dumb bomb into a smart bomb costs about $20,000. The basic problem is that artillery, which has ruled the battlefield for nearly five centuries, is not as mobile as aircraft. For the last century, as bomber aircraft became more common, artillery always had the accuracy advantage. If troops were in a tight spot and needed additional firepower nearby (to stop an enemy attack), they preferred artillery to the less accurate bombs. The smart bombs have changed that. Excalibur is an attempt to win back the accuracy advantage, for smart bombs are currently more accurate than artillery. But the cost difference will hurt artillery. Cost does matter, especially in peacetime when the army has to put up money to buy supplies of ammunition for wartime use. Building ammunition stockpiles isn't sexy and there's always a problem getting sufficient money for those purchases. The army is also putting money into more accurate rockets and missiles. The "smart rockets" (used by the MLRS system) will be cheaper than smart shells. Even missiles are getting cheaper, because the increasingly inexpensive electronics are cheaper than trying to get guidance systems to work in an artillery shell that has to be fired out of a barrel. The age of "tube artillery" (firing shells out of a barrel) is coming to an end. The cancellation of the Crusader self-propelled artillery gun was just another symptom of that.