Nuclear Testing in the South Asia

The five declared nuclear powers, i.e., USA, Russia, UK, France and China are also the only permanent members of the United Nations Security Council. This elite nuclear club also has the the privilege of veto. These powers have signed the nuclear Non-Proliferation Treaty (NPT), forbidding any technical assistance related to nuclear weapons to the non-nuclear states. 

India was a vast country with a big economy, huge population and a powerful military but without the nuclear power status. Also India had border disputes with China and it could not really confront China without becoming a nuclear power. The move for getting nuclear power status and possibly a permanent seat at UNSC was undertaken in May 1998 by doing a series of nuclear weapon tests. In turn, Pakistan replied with its own tests. The earlier Indian test of 1974 was declared as “peaceful nuclear test” and hence new tests were needed for demonstrating nuclear weapons capability. 

In May 1998, Pakistan and India announced that they have conducted underground nuclear weapon tests. Despite these claims, India and Pakistan did not get the recongnition they were hoping for. Both countries were not invited to become members of the NPT as nuclear states. Why India and Pakistan were not accepted wholeheartedly as nuclear powers? The obvious reason seems to be the planning and execution of the tests in a manner which did not permit to verify the claims made by India and Pakistan. 

Pakistan claimed that it has simultaneously fired five fission devices using Enriched Uranium as fissile material and India claimed to have tested three fission devices almost simultaneously (including a fusion device).  

Nuclear weapons are primarily meant for deterrence and national prestige. Therefore, it is important to do the nuclear test in an overt manner like an atmospheric or underwater test. Now both India and Pakistan had signed the Partial Test Ban Treaty (PTBT) and therefore they could not do atmospheric, underwater or outer space nuclear tests (unless they had pulled back from the treaty). But they had not signed the Comprehensive Test Ban Treaty (CTBT) and therefore could do the underground nuclear tests. It is incomprehensible why India and Pakistan signed PTBT when they wanted to acquire nuclear weapons. France, for example, wanted to acquire nuclear weapons and did not sign the PTBT until all the atmospheric and underwater nuclear tests had been completed.  

An underground nuclear test does not provide data on the radiation and electromagnetic pulse (EMP), which are two very important and distinct effects of a nuclear explosion. EMP can affect defense communications, air defense radars and other electronics and it was indeed an objective of a series of atmospheric nuclear tests done by USA in 1960s.  

Verification methods of a nuclear test can be improved even in the underground tests. When France was doing one of its underground nuclear tests in the desert of Algeria in May 1962, accidentally  the intense shock wave cleared the tunnel exit and the lava and other reaction gases came to surface. Lava is the keyword here.  

What is the difference between a nuclear explosion and an ordinary explosion? Both produce blast (shock waves) but the nuclear explosion also produces intense heat or thermal wave, radiation and electromagnetic pulse [1]. The intense heat and pressure melts the surrounding rock and earth into lava. The presence of lava increases the certainty that an explosion was indeed nuclear. We never read about any lava in the nuclear tests of India and Pakistan.  

The intense initial blast (shock wave) combined with thermal waves produces an artificial earthquake with a specific waveform (seismogram) which is different from natural earthquakes. The waveform or oscillation pattern depends upon many factors but the most important are the yield or power of the weapon and its type. The claims regarding yields (in equivalent kiloTons or MegaTons of TNT) were not unanimously accepted by international experts because the earthquake waveforms from the resulting explosions did not match the claims[2]. 

Pakistani tests were conducted in the granite rock mountains of Baluchistan and Indian tests were conducted in sand dunes in the desert of Rajhastan, soil types that were poorly coupled to the soil of locations where seismic stations were located. Poor coupling means a change of soil type or medium in which the seismic waves are traveling. Then the multiple explosions meant that a clean signal would not be recorded by the seismic stations. These evasion techniques, so called Decoupling, Multiple Explosions and Hide-in-Earthquake are meant for secret nuclear explosions so that they are not recorded by the seismic stations [3]. But India and Pakistan's tests were not meant to be secret and therefore the possible use of evasion techniques only raised doubts. It would seem to an analyst that they wanted to do an open nuclear test but did not want to provide technical data necessary for verification. This in itself killed the very purpose of the tests.  

To make matters worse, the seismic stations of Pakistan were disconnected from the international network before the explosion [4]. Obviously, other seismic stations around the world would record the earthquake caused by the explosion, only the signals will be weak. Pakistan should not have made its own test look suspicious in the eyes of the world community by not providing the real-time seismic waveforms from the nearest station. These things were not cleared in press releases or media communications.  

Both India and Pakistan should have invited an international body like International Atomic Energy Agency (IAEA) to inspect the test sites, confirm the claims and thus certify that these were in fact nuclear explosions and not some ordinary explosions using military grade explosives like TNT or RDX etc. When nuclear tests have been done openly, there is no harm in verification and site-inspection. This is like getting a certification. IAEA already inspects the nuclear reactors in both countries (safeguarded ones). 

Another aspect to study is the reconnaissance flights by the United States of America. When it came to nuclear weapon testing and development, United States did not spare even its close allies. In 1960s, France and China were conducting their initial nuclear weapon tests and both were subjected to intense aerial surveillance through spy flights.  

China literally launched hundreds of diplomatic protests against these spy flights and by 1971, china had launched 500 official protests [5]. France, on the other hand decided upon active measures. Mirage-III interceptors of the French Air Force could not reach the high altitudes at which the U-2 spy planes were flying (higher than 60,000 feet). To increase the operational ceiling of Mirage-IIIs, liquid-fuel rockets (called SEPR 844) were developed and put into service. These rockets were attached to the centerline pylons of the Mirage-IIIs and enabled these interceptors to fly at the required altitude for short duration. When the U-2 pilots found themselves chased by Mirage-IIIs at high altitudes, the U-2 flights came to an end and were replaced by SR-71 Blackbirds capable of even higher altitudes and Mach 3 speeds [6]. This also explains the 1960s French efforts to design and produce radar-guided air-to-air missiles like the Matra 530. Instead of designing very high altitude interceptors, it was cheaper to design radar-guided air-to-air missiles which could hit those high-altitude and high-speed spy planes. Now back to the main topic.   

It is strange that US reconnaissance planes did not fly over India and Pakistan in 1998 when they were preparing and conducting their nuclear tests (at least there were no official protests or press releases). It is true that reconnaissance satellites have largely replaced the airplanes but still satellites either do not provide round-the-clock surveillance or can't cover all areas of interest due to limits of their orbit and the number of satellites in a particular orbit. Furthermore, reconnaissance is not just limited to taking photographs. Did the US not take these programs as serious ones? If there were any spy flights, they should have been communicated to the public and it again becomes an issue of media communication. 

[1] Nuclear Weapons: Principles, Effects and Survivabililty, Charles S Grace, Brassey's. 

[2] Monitoring Clandestine Nuclear Tests, http://str.llnl.gov/str/Walter.html 

[3] Monitoring Underground Nuclear Explosions, Ola Dahlman and Hans Israelson, 1977, Elsevier.

[4] When Mountains Move – the Story of Chagai, Rai Mohammad Saleh Azam, Defence Journal, June 2000. 

[5] SR-71 Blackbird in Action, Lou Drenel, Squadron Signal Publications. 

[6] Le Fana de l'Aviation, Hors Series No.5, 2016.