Kerry admits to Senate that his negotiations with Iran are 'not legally binding'

US Secretary of State John FN Kerry told a Senate hearing on Wednesday that his negotiations with Iran over its nuclear capability are 'not legally binding.' That prompted this from Senator Tom Cotton (he of the letter to the Mullahs).

Important question: if deal with Iran isn't legally binding, then what's to keep Iran from breaking said deal and developing a bomb?
— Tom Cotton (@SenTomCotton) March 11, 2015

And here's an answer....

@SenTomCotton Nothing. And that is precisely the way the Mullahs want it.
— Pradheep Shanker MD (@Neoavatara) March 11, 2015

More here.