A SERIOUS nuclear competition between two nuclear-armed rivals is very hard to stabilise. When one rival increases its nuclear capability, the other does, too. Then both rivals feel less secure — even when they possess secure retaliatory capabilities. It’s even harder to stabilise a triangular nuclear competition, as is the case with China, India and Pakistan. A two- or three-sided competition can only be stabilised when disputes are resolved or set aside, trade increases, and rivals tacitly agree to restrain their nuclear capabilities.