Here are my information sources Gareth:

The Arms Control Association:

http://www.armscontrol.org/factsheets/cbwprolif.asp

The Federation of American Scientists:

http://www.fas.org/index.html

The Carnegie Endowment for International Peace's Non-proliferation Program:

http://www.ceip.org/files/projects/npp/npp_home.ASP

And the source of information to back up your opinions, Gareth, are...?