Q: The U.S. is trying to restrict Iran's civilian nuclear program but it is going to provide nuclear-powered submarines to Australia. Add to it Israel's nuclear weapon arsenals. Isn’t it an example of a double standard?

A: I agree that it is a double standard. However, before 2003 at least, Iran had an interest in acquiring nuclear weapons and is suspected of preserving that option (editor’s note: Iran has declared production, stockpiling, and use of weapons of mass destructions, including nuclear arms, as religiously forbidden). There is no reason at this time to suspect Australia of interest in nuclear weapons. 

Another example is Brazil, which has for decades pursued both enrichment and a nuclear submarine.  During the 1980s, while Brazil had a military government and was also interested in acquiring nuclear weapons, the U.S. applied a lot of pressure to try to stop its enrichment program.  

Since Brazil renounced nuclear weapons, made transparency arrangements with Argentina, and joined the NPT, the U.S. has been much more relaxed about Brazil’s enrichment and nuclear submarine programs.  Brazil currently is focused on using low-enriched uranium (less than 20% U-235) in its submarine reactor.