The idea of bringing all nuclear weapon states into some kind of a START-type data exchange arrangement seems to be going mainstream. Madeleine Albright and Igor Ivanov just mentioned it in their New York Times op-ed. James Acton suggested the exchange in his Low Numbers report.
It is good to see the idea that I've been advocating for some time is taking hold. Here is my March 2009 Bulletin column:
Nothing would prevent France or Britain from voluntarily assuming the same obligations that the United States and Russia have under START, in particular, its reporting and transparency requirements. They could commence by releasing data about their strategic nuclear forces in the same format that is required by START. Five states currently publish memorandums of understanding with detailed data on missiles, submarines, and strategic bombers deployed on their territory twice a year--the United States, Russia, Ukraine, Belarus, and Kazakhstan (the last three send their MOUs with mostly zeros in them). There is no reason why Britain, France, China, and eventually others can't do the same, even if they are not formally parties to START.
It is not quite correct to say that the idea was not elaborated at the time - it was, but in 2009 the START treaty was about to expire and give way to the new treaty with a completely new set of reporting requirements. Still, for those who might be interested in seeing how this data exchange might have looked like, here is a draft START MOU for France.
Now that New START is in force it does make sense to return to this idea. One problem is that New START is much less transparent than the old one - we are yet to see any data emerging from the U.S.-Russian data exchange. It's possible, of course, that this semi-secret manner of data exchange would be more attractive to France, U.K., and especially to China. I very much doubt that - these countries are more likely to point at the new found U.S.-Russian secrecy as an excuse to keep their data secret as well and the United States and Russia are not quite in a position to lobby for more openness. On the other hand, I can see how an issue like this could be discussed at the upcoming P-5 summit. If this discussion results in some data exchange between the five, whether publicly open or not, it would be a step in the right direction.
By the way, the data exchange does not have to be a privilege of the nuclear weapon states - any country that wants to support the idea could publish its own New START MOU. The format is very well described in the treaty. Norway? New Zealand? For most countries the document will contain only zeros (some would have to report space launch facilities), but there is nothing wrong with that - Belarus, Kazakhstan, and Ukraine had been doing it for years.