The recent proposal by Australia to sell uranium to India raises the question of how international law regulates traffic in nuclear weapons, and the materials and technology to make them.
In theory, the cornerstone of the non-proliferation regime is the Treaty on the Non-Proliferation of Nuclear Weapons of 1968, usually known as the Non Proliferation Treaty or NPT. Many people are uneasy about Australia's proposed change of heart, because the NPT bans signatory countries from assisting non-signatory countries with their nuclear weapons programs. Australia is a party to the NPT; India is not.
So what is the NPT about? It was signed at the height of the Cold War and contains a simple, if not necessarily fair, formula. The five countries which then had declared nuclear weapons — USA, UK, China, France and USSR (now limited to Russia) — would be allowed to keep them but would assist other signatories to develop nuclear energy for peaceful purposes under the supervision of the International Atomic Energy Agency (IAEA). These non-nuclear signatories include Australia — commonly thought to have the world's largest uranium reserves.
By collateral agreements, the nuclear-armed countries would guarantee the security of any other signatory to the NPT from any nuclear strike.
Needless to say, the reality has not been that simple. The nuclear powers have not abolished their nuclear arsenals and have, indeed, occasionally threatened non-nuclear parties to the NPT with nuclear attack.
In 2002 and 2003, for instance, Geoff Hoon (then Britain's defence minister) threatened to use them against 'rogue states' using battlefield 'weapons of mass destruction'. (The latter is a political, rather than a legal, term but is generally thought to include at least nuclear, chemical and biological weapons.) In 2006, French President Jacques Chirac threatened nuclear attack against states supporting terrorism or developing WMDs.
There are also a growing number of non-parties to the NPT with nuclear weapons. Israel, India and Pakistan never signed the treaty, while North Korea (which has now successfully tested at least two nuclear weapons) withdrew in 2009.
Most of these non-parties see few benefits to joining. It is one thing to threaten a country which may be developing 'weapons of mass destruction' (remember the oft-repeated justification for invading Iraq in 2003). Attacking a country that actually has them is quite another proposition.
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