The entire world sits there and lets the insane leader of Iran build a nuclear weapon with the avowed purpose of using it without provocation. If they let him do what he says he will do, the planet will look very different on day after. In a nuclear / thermonuclear exchange there will be no real survivors, just victims; some early-on, most over a longer term. It is an ugly picture to contemplate.
Well, at least our good friends and trading partners, China is doing something about it. /s