It seems the marathon negotiations concerning the future of Iran's nuclear capabilities have wound down for now, according to Der Spiegel:
This morning the representatives of Iran, Germany, and the UN-veto-powers [China, France, Russia, UK, US] sat down again at the negotiating table in Lausanne- but after a short time Russia's representative Sergei Lavrov left the meeting. This was announced by the Russian Foreign Ministry according to information from AFP.
According to the same article, China's foreign minister Wang Yi is more skeptical than yesterday evening:
In this end phase all parties must be ready to draw closer in their positions.
This does not mean the end of talks, however. The deadline for reaching an agreement between all parties has been extended until June. With Laurent Fabius leaving the talks earlier but prepared to return when it is useful for him to be present, the suggestion seems to be that the points of disagreement remain primarily between the chief stakeholders: the US, Russia, and Iran.
If it is true that an agreement with Iran is popular in the US, then perhaps now is yet again the time for those who support such an agreement to make their voices heard.
It is my sincerest hope, for the benefit of the entire world, that a lasting agreement can be reached.