The Pentagon is always studying new weapons, relatively few of which actually end up in service. The latest new idea under study is a Trident-D5 submarine launched missile with its nuclear warheads replaced by bunker-busting conventional deep penetrating weapons. These could burrow deep into rock and concrete and then collapse the kind of command and control bunkers and nuclear storage sites that have been built around the world to avoid being destroyed by US precision-guided bombs. (US intelligence knows of 1,400 such bunkers.) Each Trident has eight independent nuclear warheads; some conventional Tridents might carry that many to attack bunker complexes while other missiles might have only a single warhead to target a terrorist hideout. This weapon would have several advantages over aircraft- delivered munitions. An enemy, such as North Korea or Iran, would not know that such a submarine was even in the area until the missiles launched, at which point there could be only a few minutes until impact. The speed of the missile (which is vastly higher than the speed of any bomber) aids in penetration of rock and concrete, and makes the weapon much harder to stop with Russian-built S-300 anti-aircraft missiles. With such a short flight time, "fleeting" targets could be destroyed before they could move. The Bush Administration has already asked Congress for $30 million for a three-year study of the concept. Some of the money would go to improving the accuracy of the nuclear version, and that improvement would be directly applicable to the conventional design. Some of them could be carried by the four older Trident subs being converted to carry cruise missiles. The cruise missiles have a range of only 1,000 miles, but a D5 can reach 4,000 miles. The US might also replace a few of the nuclear D5s on all submarines with conventional missiles, giving a multi-spectrum response capability. Such a weapon would also prove controversial. Subs able to fire it could also fire the nuclear version, which would count against any treaty limits (something the Bush Administration is not too concerned about), and the launch of such a missile could (if detected) be mistaken for a nuclear-armed missile aimed at another country. There is also the traditional problem that only half of the submarines are at sea at any given moment, so you have to buy extra missiles in order to have the required number available. A conventional D5 could compete for funds against another weapon being developed to attack deep bunkers, that being an Army-led program to load a penetrating warhead on an Army ATACMS missile. That weapon, however, has a much shorter range and its launchers would be more easily spotted by an enemy. The D5 program might actually borrow technology from the ATACMS
variant.--Stephen V Cole