Signed agreements with guarantees following lengthy negotiations have always been the way 'high stakes' deals / partnerships have been conducted between nations, it is just that the US and a couple of other countries have become so used to 'telling' middle eastern nations what to do they have fogotten this. Iran is not being unreasonable in any way. It is showing the world that it is a tough negotiator in the face of a global bully who traditionally either 'buys', 'occupies', 'destabalises', or 'invades' middle east countries who do not submit to its will. Iran has also shown considerable resiliance under actual sanctions - with the threat of further sanctions and even military action. Most other countries would have, and indeed have, 'capitulated' under such pressure. Once the US, UK, Israel, and a few other nations realise that they must negotiate with Iran as an equal partner - and stop viewing this ancient and proud nation as a primitive, backward, and weak country that must bow down before the military might of the west, relations will fly forward and the US may very well get some of that lovely Iranian oil it really wants without firing a shot.