Nuclear War Planning in Japan
Perhaps more surprising than the routine introduction of nuclear weapons onboard warships and aircraft is the fact that part of the U.S. nuclear warplan itself (SIOP) was built and maintained at Fuchu Air Station. Moreover, facilities in Japan were routinely used for nuclear Command and Control operations to exercise this warplan.
The SIOP was the first attempt to bring together under a single coordinated plan the numerous nuclear strike plans of the ever-increasing number of nuclear weapons assigned to ships, submarines, aircraft, and land-based missiles. Incorporating the objectives and guidance of the National Strategic Targeting and Attack Policy, the SIOP governed all attacks on all targets listed in the National Strategic Target List (NSTL). It determined the targets to be attacked, the efforts to be expended against each target consistent with the value or the target, and integrated individual strikes for mutual support through the establishment of attack corridors, timing, and by other means.199
In the Pacific, the activation of the SIOP had a major impact on nuclear war planning and necessitated major revisions of nuclear war plans in the region. Besides the task of maintaining up-to-date intelligence upon which to base revisions to the target list, and planning for use and delivery of weapons, approximately 30 members of CINCPAC's staff were engaged in analyzing existing plans and conducting war games on the PACOM portion of the SIOP. CINCPAC maintained permanent representation with the Joint Strategic Target Planning Staff at the Strategic Air Command's Omaha headquarters, as well as other representatives who served there on a temporary basis.200
The most important change involved CINCPAC's General War Plan (OPLAN 1-61), which contained the plans for use of U.S. forces in a general war with the Soviet Union in the period April 1961 to June 1962. OPLAN 1-61, which replaced CINCPAC's General Emergency Operation Plan 1-58 from 1958, included 10 annexes, one of which (Annex E) contained the Nuclear Planning Data and Target Lists for General War. The annex defined the targets to be destroyed during the initial nuclear attack and those targets that would require a pre-described level of destruction or neutralization during operations following the initial nuclear attack.201
Another major change involved Operations Plan 23-61 (OPLAN 23-61), which contained the plans for U.S. military operations in support of British forces during a forced withdrawal from Hong Kong. If China attempted to push out Britain with military force, the U.S. Pacific Command would if necessary respond with nuclear weapons. The nuclear annex (Annex E) to OPLAN 23-61 was completed in December 1961.202
A third change occurred in Operations Plan 27-60, which governed the defense of South Korea. OPLAN 27-60 was based on the Joint Chiefs of Staff Joint Strategic Capabilities Plan, and the Unified Command Plan. It was also based on UN resolutions regarding UN military assistance to South Korea, the Mutual Defense Treaty, and other agreements between the U.S. and the South Korea, as well as the Declaration of the Sixteen Nations Relating to the Armistice from July 1953. OPLAN 27-60 also provided for the use of nuclear weapons in the event of renewed communist aggression against South Korea, and a new nuclear annex (Annex E) was completed in August 1961. Despite the inclusion of nuclear forces in OPLAN 27-60, CINCPAC remarked that "the extent of operations in Korea are not to prejudice the primary task of securing Japan, Okinawa, and the Philippines."203
The perceived threat to Japan was important for the Japanese government's attitude towards U.S. nuclear operations in Japan. During U.S. preparations for two high-level talks between the U.S. Ambassador and the Japanese government in early 1963, the Ambassador made numerous references to the Chinese Communist threat to Japan. Yet CINCPAC intelligence believed that this threat had been overrated, considering that the prime threat was the Soviet Union. The overt threat to Japan would occur only in a general war situation, CINCPAC intelligence concluded, and would be primarily a Soviet threat.204
The SIOP Planning
The SIOP depended upon reliable Command and Control facilities in Japan and upon the cooperation with Japanese defense forces. Some of the Command and Control facilities were located in Japan and on Okinawa. Following the nuclear exercise High Heels II in September 1962, for example, which was the "most successful test of PACOM's communications system to date," two facilities listed for inclusion in Defense Communication Agency (DCA) Mid-Range Plan included Camp Drake, Japan, and Fort Buckner in Okinawa.205
In some cases, joint U.S.-Japanese exercises even involved nuclear operations. One of three air defense exercises held during 1962 with the Japan Air Self Defense Forces (JASDF), for example, had the objective to test coordinated air attack, air defense capability, and "nuclear broadcast procedures." The exercise included forces from the Pacific Air Force, 7th Fleet, Strategic Air Command (SAC), and the JASDF.206
The use of bases in Japan for strategic nuclear command and control operations continued in the mid-1960s when Yokota Air Base, together with Clark Air Base in the Philippines and Kadena Air Base in Okinawa, was designated as a dispersed operating site for Strategic Air Command's (SAC) new airborne command post aircraft. These specially equipped EC-135 aircraft, code-named Blue Eagle, would be kept airborne in a crisis to ensure continued command and control of U.S. nuclear forces despite a Soviet nuclear attack. During September 1965, Blue Eagle aircraft visited Yokota Air Base, as well as Clark Air Base and Kadena Air Base.207 During routine operations (DEFCON 5 and 4), Battle Staff Teams would make an average of three deployments a month to Blue Eagle support facilities in Japan, Okinawa, and the Philippines. Under increased defense conditions, deployment of staff and aircraft to the dispersal sites would escalate.208
Before long, however, not only would U.S. bases in Japan be used to support the SIOP, but part of the nuclear war plan itself was actually built there. In 1967, CINCPAC established the Pacific Operations Liaison Office (POLO) in Fifth Air Force facilities at Fuchu Air Station. POLO was responsible for the production of various planning documents for the execution of the SIOP. It also built PACOM's SIOP Reconnaissance Plan (Preplanned Reconnaissance Pacific (PRERECPAC)), and functioned as the nuclear operations liaison in the Western Pacific area. One of the branches at POLO was the Deputy for Command Center and Nuclear Operations branch, which included the Airborne Command Post Branch and the Nuclear Operations/Safety Branch.209
Planning and maintaining the nuclear war plans was a continuous and time-consuming process, and Fuchu Air Station was a frequent host for SIOP planning conferences. In October 1966, for example, CINCPAC directed his PACOM Operations Liaison Officer to hold the fifth annual PACOM Reconnaissance Conference at Fuchu Air Station. The conference planned and coordinated the use of reconnaissance assets under the SIOP to maximize target enemy coverage.210
As SIOP planning became more computerized and flexible, the need to located part of the function in Japan disappeared. Eventually, POLO was disestablished on July 15, 1972 in order to permit elimination of the Fifth Air Force's redundant and costly automated data processing facility at Fuchu, and the SIOP functions transferred to facilities at Kunia in Hawaii.211
While the nuclear port visit debate raged in public, routine maintenance of the nuclear war plan was maintained in secrecy throughout the 1970s. In October 1974, for example, CINCPAC conducted a review of its emergency action procedures. In addition to Japan (and Okinawa), the team visited Guam, Korea, the Philippines, and Taiwan to inspect the nuclear war fighting capability of facilities in those locations. This included: Command, Control, and Communications (C3) systems; the PACOM alert notification systems and procedures; the use, control, and storage of Sealed Authenticator Systems (SAS); emergency action procedures; and All-Source Information Center (ASIC) procedures. Units of interest were SIOP units, Emergency Action Message relay stations, command centers, and ASICs.212
Nuclear Command And Control Operations
Likewise, CINCPAC's Airborne Command Post (ABNCP), called Blue Eagle, exercised Command and Control of nuclear war during a number of deployments to Japan. Continuous air-borne alert had been canceled in January 1970 due to cost, and the aircraft maintained on a ground alert capable of taking off on short notice. In 1974, however, CINCPAC introduced a new "deployed ground alert" concept, in which Blue Eagle held random 24-28 hour ground alert watch periods in conjunction with bi-monthly deployments to forward airfields in the Western Pacific. Deployed ground alert periods were randomly scheduled to Yokota in Japan and Kadena on Okinawa, as well as to Clark Air Base in the Philippines and Ching Chuan Kang Air Base in Taiwan. By the end of 1974, a total of 20 deployed ground alerts to these bases had been carried out.213
A special objective of these deployments during 1974 involved the maintenance of communication with selected nuclear ballistic missiles submarines and nuclear-armed aircraft carriers deployed near Japan. The Navy normally used its own TACAMO C-130 aircraft for this function, but resources for TACAMO aircraft had been temporarily reduced. Yokota and Kadena (as well as the Clark and Kang air bases) had been chosen because they bordered the patrol areas for the ballistic missile submarines. From one of these bases, the Blue Eagle aircraft could quickly reach an operational orbit within VLF/LF/HF range with the capability to relay SIOP emergency action messages to the submarines.214
Testing of the system had begun in February 1973, and through January 1974 a total of 21 missions had been flown to maintain SIOP communication with the strategic nuclear submarines. The tests, however, demonstrated that communication could not be guaranteed. Best reception was in range up to 1,200 nautical miles, but during the 21 missions flown, only 12 reports had been received from the submarines. Analysis of 40 SSBN reports indicated that they had only received 21 emergency action messages. The overall success rate from the aircraft to the submarines was 52.5 percent. Testing continued through the year, usually with three operations a month to selected submarines, aircraft carriers, and Naval Communications facilities in Guam, Japan, and the Philippines.215
Throughout the 1970s, Blue Eagle deployed ground alert exercises to Japan continued. In 1975, for example, Blue Eagle conducted ten deployed ground alert exercises at Kadena (Okinawa) and Yokota Air Base in Japan, and at Clark Air Base in the Philippines.216 Routine deployments to Yokota and Kadena continued in 1978, and in September that year, the Japanese Defense Agency Command Center Overseas Study Team visited the airborne command post.217 Again, during 1979, Yokota and Kadena were among four bases in the Pacific receiving "the most frequent" airborne command post visits.218
Just as strategic nuclear submarines had exercised with airborne command post aircraft around Japan in the 1970s, strategic nuclear submarine operations continued throughout the 1980s. One tragic reminder came in April 1981, when the strategic nuclear submarine USS George Washington (SSBN-598) collided with the Japanese merchant vessel Missho Maru while "on routine operations" only 110 miles south-southwest of Sasebo, Japan. Two Japanese crew members were killed and another 13 rescued by Japanese destroyer after the Missho Maru sank.219
The incident sparked a political furor in Japan, straining U.S.-Japanese relations only a month before a scheduled meeting between Prime Minister Zanko Suzuki and President Ronald Reagan. The United States was criticized because it waited 24 hours before notifying the Japanese authorities. After two days of furor, President Reagan and other U.S. officials expressed regret over the accident but refused to say what a strategic submarine was doing so close to Japan (only 20 miles outside the 12-mile limit) or whether it was carrying nuclear missiles.220
Airborne Command Post aircraft deployments to Japan continued throughout the 1980s and have continued into the 1990s. In December 1991, for example, a ABNCP aircraft deployed to Yokota Air Base in Japan and Cubi Point in the Philippines to provide alternate command authority (ACA) to the region.221 Again in November 1992, an EC-135 aircraft deployed to Kadena Air Base in Japan and Osan Air Base in South Korea. During the deployment, battle staff training "covered all facets of the SIOP and theater nuclear [Command and Control]." Moreover, site surveys were conducted at each location to determine the feasibility of using those locations as Alternate Command Facility (ACF) sites. While Osan AB was found to be only marginally satisfactory, logistics support for the deployment at Kadena AB was considered "outstanding."222
Communication Facilities
In addition to such operational deployments, the U.S. also established a number of unique communication facilities in Japan that supported execution of U.S. nuclear war plans. This included Defense Satellite Communications System (DSCS) facilities that were one of the major components of the World Wide Military Command and Control System (WWMCCS) that provided the means for the U.S. National Command Authorities (NCA) and subordinate commands to direct U.S. nuclear and non-nuclear forces. DSCA ground stations were installed at Camp Zama near Tokyo in 1981, at Fort Buckner on Okinawa, and at Misawa Air Base at Honshu.223
By the mid-1980s, Japan had become the host to the most extensive U.S. nuclear infrastructure in the Pacific with over two-dozens sites housing nuclear related facilities. Four of the U.S. Navy's six facilities designed to contact submerged submarines via very-low-frequency (VLF) transmissions, for example, were located in the Pacific; one of these was at Yosami in Japan. Moreover, four of five specially converted LORAN-C navigation beacons for communication with nuclear Trident submarines in the Pacific were located in Japan.224
These facilities were frequently involved in exercises that simulated execution of nuclear war plans. During the CINTEX-CRIMEX 85 exercise in February-March 1985, for example, the Seventh Fleet took part in an evaluation of the WWMCCS during a simulated period of deteriorating international political-military relations resulting in a large-scale conventional war and limited use of tactical nuclear weapons.225 Already by the early 1990s, however, the DSCS's capacity was already proving too limited to handle the ever-increasing amount of Command and Control data.226
The Nuclear Offload
The endless battles with non-nuclear countries over nuclear port visits, along with the overall thaw in the Cold War, gradually eroded the justification for maintaining tactical nuclear weapons at sea. During Congressional hearings in 1988, the U.S. Navy had pledged its commitment to modernizing its nuclear stockpile "through vigorous and sustained efforts."227 But behind the scenes the Navy had already taken its first steps toward a denuclearization of its combat fleet.
In early 1989, the U.S. Navy acknowledged that it had decided to scrap three tactical nuclear weapon systems: the ASROC ship-launched anti-submarine rocket; the SUBROC submarine-launched anti-submarine rocket; and the Terrier ship-launched anti-air missile. As a result, nearly 1,200 nuclear warheads would be removed from 142 ships and 27 submarines. While the move dramatically reduced the number of nuclear-capable ships, another 2,490 non-strategic nuclear weapons would remain in the fleet.228 The withdrawal of ASROC, SUBROC, and Terrier nuclear warheads was completed in early 1990.
Meanwhile, pressure was building in the White House for a complete removal of tactical nuclear weapons from the fleet. President Bush's national security advisor, Brent Scowcroft, reportedly "leaned on" Defense Secretary Richard B. Cheney to eliminate the weapons in an effort to undercut growing opposition in Scandinavia, the Pacific, and the Far East to nuclear port calls. Senior aides to Cheney, who opposed removal of nuclear cruise missiles from submarines, were overridden when Admiral Frank Kelso, the Chief of Naval Operations, made it clear that he did not object.229
On September 9, 1991, the idea had progressed so far that CINCPAC ordered his component commanders and the Commander for U.S. Forces in Korea to study the role of non-strategic nuclear forces in the Pacific. In doing so, CINCPAC reminded that non-strategic nuclear forces had played an important role in U.S. policy since the Korean War. Although their principle rationale related to the U.S.-Soviet Cold War confrontation, he pointed to new threats in the future, including the break-up of the Soviet Union, the refocus of U.S. national military strategy on regionalism and forward presence, the resurgence of ethnic and cultural conflicts, and the proliferation of weapons of mass destruction.230
But events evolved too fast for any study. Only two days later, on September 11, the CJCS directed CINCPAC to develop a plan for the removal of nuclear artillery projectiles, nuclear Tomahawk cruise missiles, nuclear strike bombs, and nuclear depth bombs "at the earliest opportunity."231
Then, on September 27, 1991, President Bush announced that all nuclear weapons would be offloaded from U.S. Navy surface ships and attack submarines and all ground-based nuclear weapons would be withdrawn to the United States. "From Saturday on," Pentagon spokesperson Pete Williams said shortly after the announcement, "no U.S. Navy surface ships or attack submarines have deployed from their ports with any tactical nuclear weapons on board."232
The move solved the Japanese dilemma. Not only had the U.S. government announced in public that nuclear weapons would no longer be present on surface ships and attack submarines. It also said there would no longer be a need for a Neither Confirm Nor Deny (NCND) policy for the vessels, the practice that had so complicated the relationships with Japan and numerous other countries around the world. The NCND policy would remain in effect, however, for strategic submarines and for bases and Air Force facilities where nuclear materials are stored "for obvious security reasons," the Pentagon said.233 For naval forces, a "modified" NCND policy was ordered:
It is general U.S. policy not to deploy nuclear weapons aboard surface ships, attack submarines, and naval aircraft. However, we do not discuss the presence or absence of nuclear weapons aboard specific ships, submarines, or aircraft.234
"A major step forward to the ultimate elimination of nuclear weapons," Japanese Prime Minister Toshiki Kaifu said modestly.
Warships that had sailed on overseas deployments even a few days before the announcement still carried their nominal load of nuclear weapons. At the time of the announcement, the U.S. Navy had several hundred nuclear strike bombs and depth charges onboard half a dozen aircraft carriers. Another 100 or so nuclear-tipped Tomahawk cruise missiles were onboard attack submarines, cruisers, and destroyers. The USS Eisenhower (CVN-69) battle group, for example, had departed Norfolk Naval Base on the U.S. East Coast barely a week before the announcement. It carried a standard loadout of 100-120 nuclear bombs and depth charges onboard the carrier, and several nuclear Tomahawk missiles onboard the submarines, cruisers, and destroyers in the group.238
Despite the offload, CINCPAC was initially directed to retain the capability to regenerate and/or re-deploy naval nuclear weapons in a timely manner, and to ensure that storage and other necessary support infrastructure was maintained. Nuclear annexes to Operational Plans and non-SIOP options were to be maintained, and the annexes should include planning factors, timelines, and rationale to regenerate and/or re-deploy sea-based tactical nuclear weapons systems.243
For the surface fleet, however, the option to re-deploy nuclear weapons ended only a few years later, when the U.S. decided as part of the 1994 Nuclear Posture Review that surface ships and aircraft carriers should no longer have the capability to carry nuclear weapons at all. For cruisers and destroyers this meant loosing the ability to carry and launch nuclear-tipped Tomahawk cruise missiles. For the aircraft carriers, this means that for the first time since the 1950s, flat-tops were no longer part of the U.S. nuclear strike force. Only attack submarines would continue to train and plan nuclear Tomahawk missions, although their weapons would be stored on land under normal circumstances.
The benefits from these events to the Japanese government were immediate not only because of the U.S. initiative itself, but also because other nuclear powers operating in the waters around Japan soon followed suit. In connection with the arrival of the Royal Navy aircraft carrier HMS Invincible to Yokosuka in July 1992, for example, the British Embassy in Tokyo readily confirmed in a letter to the Japanese Peace Resources Cooperative that Royal Navy ships and aircraft "no longer have the capability to deploy nuclear weapons."244 Japan's nuclear battle was finally over.
