John Kerry actually said...

Iran's leaders need to understand that the full weight of the international community will bear down on them if Iran continues to defy the U...

So we need to understand also and Iran needs to understand that the talks that we envision will not be a substitute for Iran's requirement t...

We need to convince Iran that it would in fact be worse off were it to succeed in developing a nuclear weapons capability.

Thus far, that multilateral process has not worked, in part I believe because there has not been solidarity among the P5+1.