- South Africa: The apartheid government of South Africa shut down its nuclear weapons program for a couple reasons. Government officials were afraid of a post-apartheid government armed with nuclear weapons and South Africa had no nuclear armed enemies.
- Argentina and Brazil: Basically, both countries realized they did not need strategic weapons and could develop mutual trust through bilateral inspections. They however rejected the nuclear nonproliferation treaty and interference from other countries (i.e. the international community).
- Ukraine, Belarus and Kazakhstan: Basically, these countries realized that they needed to focus on their economies and that having nuclear weapons made them targets in a NATO-Russia war. They signed onto the NPT in exchange for economic concessions from the United States.
- India and Pakistan: Basically, both India and Pakistan flatly rejected international norms and developed nuclear weapons. They however limited their development of nuclear weapons after they proved they could get them to work, enough to deter each other.
- North Korea: North Korea has developed several nuclear weapons while negotiating its own nonproliferation with the international community, its regional neighbors and the United States.
Looking at these several case studies, it is impossible to conclude that international norms against proliferation have had a decisive effect in preventing the proliferation of nuclear weapons. It appears that countries do not suspend nuclear weapons programs because they have come around to thinking that their program is bad form or inappropriate.
That said, international norms have made a contribution in some ways. The Nuclear Nonproliferation Treaty, Comprehensive Test Ban Treaty and IAEA inspections provide examples of international cooperation that other countries can follow from. Although Argentina and Brazil expressly rejected “international” norms, their decision to set up bilateral inspections is very reminiscent of IAEA inspections. Although Ukraine, Belarus and Kazakhstan used the signing of the NPT as a bargaining chip. This bargaining chip provided a tangible goal for these countries and demonstrated what nonproliferation could look like.
All in all, international norms and the international agreements that represent them make modest contributions to nuclear nonproliferation. None of the countries discussed limited their nuclear weapons programs explicitly because of international norms. However international norms are generally positive elements even when countries use them for their own self-interest. Furthermore, it seems that nonproliferation is usually the result of several factors and not just one.
As the world's lone super-power and a leader in the field of nonproliferation it is the responsibility of the United States to lead the development of international norms against proliferation. Unfortunately, the United States has often taken steps that undermine the development of these international norms. The United States is currently develop bunker-busting bombs, which some politicians think should have low-yield nuclear warheads. The United States continues to conduct sub-critical nuclear tests, which is most likely for nuclear weapons research. The United States has changed its seismic activity data to cover up nuclear tests. Some American politicians are against more missile reduction treaties with Russia. Although the United States is quick to tell other countries to fulfill their international obligations it has no inherent desire to do the same. The United States has not internalized norms of nonproliferation. Whether this is hypocritical or not is not the point. The United States uses international norms as a tool in negotiations. The United States is self-interested, just like any other nation, and this should come as no surprise. However, it is in the US self-interest to follow most international norms on nonproliferation. The United States reporting its seismic data truthfully, refraining from certain sub-critical nuclear tests, and reducing its plethora of nuclear-armed missiles gives it narrative justification for demanding that other nations do the same, especially Iran.
The previous case studies have shown that international norms are unlikely to be decisive when it comes to nonproliferation. However, they generally provide positive effects and should therefore be encouraged by the United States.
* Admittedly, I based my argument on the evidence I have seen. If there is evidence that leads to another conclusion, I would very much like to see that.