An RNEP is not the same as a "mini-nuke" or low-yield nuclear weapon. The defense authorization bill of fiscal year 1994 prohibited the US from conducting research into low-yield nuclear weapons, defined to be weapons having a yield of five kilotons or less. An RNEP has a yield up to a megaton (1000 kilotons), 70 times the size of the Hiroshima bomb.
In theory, these weapons have reduced nuclear fallout due to the immediate burial of the weapon. However, underground testing has revealed a "chimney" or "smokestack" effect, where fallout leaks through the roof of the cavity created by the explosion.
Bunkers can be constructed farther into the Earth to make them more difficult to reach. If a tunnel can be built 300 m into the side of a mountain, then it can be effectively built 1000 m into the mountain. The RNEP's attack range would only be limited to entrances and ventilation openings, which conventional weapons can easily handle. There would be no need for a nuclear weapon.
At the Nevada Test site, the depth required to contain fallout from a nuclear test is between 100 and 500 meters. Current US weapons penetrate up to 30 meters. Thus, fallout would not be completely contained.
Many feel that it is hypocritical for the United States to be prohibiting other countries from obtaining nuclear weapons while it develops more powerful bombs. Development of the RNEP, critics say, would further a new global arms race.
In October 2005, the Bush administration and the Senate announced they agreed with the position of House Representative David Hobson on eliminating research funding for the RNEP in the Energy and Water Appropriations bill of fiscal year 2006.
The focus will now be with the Defense Department and its research to earth penetrating technology using conventional weaponry. The NNSA [National Nuclear Security Administration] indicated that this research should evolve around more conventional weapons rather than tactical nuclear devices. With this department change in policy, we have agreed not to provide DOE with funding for RNEP.
Senator Peter Domenici, Chairman of the Senate Energy and Water Development Appropriations Subcommittee, 25 October 2005
"It's immoral, it's wrong, it's unethical...it's hypocritical for us to say to other countries-North Korea and Iran-don't get the bomb and yet we're making new types... It just undermines everything..." - listen
"...so right now we're in a holding pattern, quite frankly, as far as moving forward on nuclear disarmament...." - listen
Reverend Robert Moore, Executive Director, Coalition for Peace Action
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