During the Cold War, the focus of U.S. nuclear policy was deterring or retaliating in responseto a Soviet nuclear attack. U.S. nuclear forces were designed and sized for that contingency. Othercontingencies in which the United States might have used nuclear weapons were much more remote,and would have required far fewer nuclear weapons, than responding to a Soviet attack. Defenseplanners dealt with them, but as "lesser included cases" not requiring new weapons. The end of the Cold War led to a reduction of the U.S. nuclear weapons development effort. The first Bush Administration halted nuclear testing except for safety and reliability of the nuclearstockpile, canceled weapons that were under development, and withdrew most U.S. battlefieldnuclear weapons. Numbers of personnel in the nuclear weapons complex -- the facilities managedby the Department of Energy (DOE) to develop, test, manufacture, and maintain nuclear weapons-- dropped sharply. At congressional direction, the United States began a moratorium on nucleartesting in October 1992 that is still in effect and worked to negotiate the Comprehensive Test BanTreaty (CTBT), a ban on all nuclear explosions. Before the moratorium, the United States conductednuclear tests on an ongoing basis; with the end of testing, the Clinton Administration changed thetest readiness posture to 24 to 36 months. The George W. Bush Administration came into office with a different stance on nuclear weapons policy, which the September 11 attacks stiffened. It delivered a Nuclear Posture Review(NPR) to Congress in December 2001. (3) Thisclassified study, mandated by legislation, (4) spelledoutthe Administration's views on the role of nuclear weapons. A strategic relationship with Russiabased on the threat of mutual annihilation had become "very inappropriate," (5) according to J.D.Crouch, Assistant Secretary of Defense for International Security Policy, and the threat had becomemore diffuse. The NPR focused on nuclear capabilities deemed needed for various contingenciesrather than mainly to counter the Soviet nuclear threat. That is, the Administration perceived a widerrange of possible uses for nuclear weapons quite different than the U.S.-Soviet nuclear war scenariosthat dominated Cold War strategy. Crouch said, "The capabilities-based approach argues that theremay be multiple contingencies and new threats that we have to deal with. We're focusing on howwe will fight ... not who or when." (6) To support thisapproach, the NPR envisioned a "new triad" --strike forces (nuclear and nonnuclear); defenses; and an infrastructure better able to respond tomilitary needs -- tied together by command and control, intelligence, and planning. The goal wasto "assure allies and friends" that the United States had "credible non-nuclear and nuclear responseoptions," "dissuade competitors" through a "diverse portfolio of capabilities [that] denies payofffrom competition," "deter aggressors," and "defeat enemies." (7) The NPR called for retaining the capability to deter or respond to a variety of contingencies, and for retaining Cold War-era nuclear weapons, at lower levels, to do so. With the demise of the SovietUnion and the September 11 attacks, a subset of targets -- terrorist-related facilities, some of whichhad existed for decades -- assumed greater prominence. One example is hardened and deeplyburied facilities. Rogue (and many other) states have built such facilities, which might house leadersand key communications facilities. Another example is facilities -- some deeply buried, others not-- for producing or storing weapons of mass destruction (WMD). The end of the Cold War also led to changed constraints on use of nuclear weapons. In anuclear war with the Soviet Union, assuring the immediate destruction of thousands of targets of allsorts would have been critical to national survival. Reducing fallout and "collateral damage," ordamage to people and things that were not the intended targets, was secondary in importance toachieving required probabilities of damage on targets. Warheads were typically designed to achievethat primary goal. Now, nuclear weapons to hold at risk specific, limited targets in rogue states ina credible manner are judged to need several characteristics: They would need to be able to counter threats that rogue states might pose, such as hard and deeply buried facilities or production facilities for WMD. Weapons to attack buriedfacilities would have different characteristics than weapons to defeat chemical and biologicalagents. They would be better able to minimize ( not eliminate) collateral damage consistent with military objectives. While this has long been a goal of U.S. nuclear policy, earthpenetration and increased accuracy sharply reduce the yield needed to destroy a target, making itmore feasible to attain that goal. They would need to be available readily, if not immediately, because thespecific threat might become known with little warning. They could be few in number. While an all-out nuclear attack on the Soviet Union would have struck thousands of targets, the option of an attack on a rogue state might involvea handful of targets. According to the National Nuclear Security Administration (NNSA), (8) "The Administrationbelieves the broader range of capabilities of a nuclear stockpile with these weapons will serve as amore credible, and hence more effective, deterrent than the Cold War stockpile we have today. Thismore effective deterrent will make the use of nuclear weapons less likely." (9) Some critics believe that the only use for nuclear weapons should be to deter and, if necessary, respond to the use of nuclear weapons against the United States. (10) They oppose attempts to developnuclear weapons with lower yield and reduced collateral damage as blurring the distinction betweenconventional and nuclear weapons. Even U.S. use of a low-yield atomic bomb, they assert, wouldresult in a firestorm of protest and worldwide opprobrium. Further, they believe that the U.S. nuclear arsenal has long been sufficient against a range of threats. Hardened and deeply buried targets (HDBTs), for example, have existed for decades, yetthe first Bush Administration halted work on nuclear weapons then under development and haltednuclear testing except for safety and reliability, effectively bringing work on new weapon types toa close. Presumably that administration would not have taken these steps had it envisioned a needfor new weapon types. The United States needs the active support of the entire international community in the war against terrorism, many observers believe. Assistance may take many forms: providing informationto the CIA on suspicious individuals, safeguarding shipping containers, securing radioactivematerial, or closing bank accounts of suspected terrorists. Other nations will be more likely tocooperate on issues important to the United States, it is argued, if the United States cooperates withother nations on issues important to them. One such issue is nuclear nonproliferation. The UnitedStates pledged in the Nuclear Nonproliferation Treaty (Article VI) "to pursue negotiations in goodfaith on effective measures relating to cessation of the nuclear arms race at an early date and tonuclear disarmament." In addition, as an inducement in securing international support for extendingthe treaty indefinitely, the United States and other nuclear weapon states pledged in 1995 to supportthe CTBT. (11) They made a similar statement atthe 2000 NPT review conference. (12) Critics maintain that the Administration's nuclear initiatives are at odds with these pledges. They argue that developing new or modified weapons runs counter to the NPT pledge and that suchweapons will ultimately require nuclear testing to ensure that they work. Reducing the time toconduct a nuclear test supports a future decision to test and, to the critics, implies an intent to test. These positions may harm U.S. security by undermining efforts to make worldwide cooperation onnonproliferation of nuclear and other WMD more effective. Even if some steps might be innocuousby themselves, critics believe that many around the world will see the confluence of them as piecesof a single policy and will infer that the United States is now much more willing to consider usingnuclear weapons. As an example of international concern over the new U.S. policies, the foreignministers of the New Agenda Coalition (Brazil, Egypt, Ireland, Mexico, New Zealand, South Africa,and Sweden) issued a statement that said in part, 4. The Ministers stressed that each article of the NPT is binding on the respective States parties, at all times and in all circumstances... 7. The Ministers reiterated their deep concern at emerging approaches to the broader role of nuclear weapons as part of security strategies, includingrationalizations for the use of, and the development of new types of nuclearweapons. (13) These positions may undermine U.S. security, critics fear, by spurring nations that might be targets of a U.S. nuclear attack to step up their efforts to acquire nuclear weapons. Of the three"Axis of Evil" nations, Iraq, the first target of a U.S. attack, did not have nuclear weapons as far asis currently known. Having nuclear weapons to deter the United States may be a consideration forNorth Korea and Iran, both of which apparently have active programs to produce fissile material. North Korea has stated that it has several nuclear weapons; while Iran has declared that its nuclearprogram is for peaceful purposes, few in the United States believe that assertion. Even in military terms, critics argue, nuclear use would offer marginal to negative value. Deeply buried targets could be defeated (not necessarily destroyed) with conventional weapons,destruction of entrances and air shafts, or demolition by special forces. The effectiveness oflow-yield nuclear weapons for destroying biological or chemical agents is uncertain, as discussedbelow, and intelligence might be unable to locate targets in underground complexes, as recent effortsto find Iraqi WMD showed, rendering nuclear weapons of any yield of little use. Nations couldcounter earth penetrators by burying facilities more deeply.