The United States cannot proceed unless the nuclear program is abandoned. Rouhani understands that, but he must have and end to sanctions and a return of Western investment to Iran in exchange. These are doable under the current circumstances. The question of Iranian support for al Assad is not really an issue; the United States does not want to see a Syrian state dominated by radical Sunnis. Neither does Iran. Tehran would like a Syria dominated by al Assad, but Iran realizes that it has played that card and lost. The choices are partition, coalition or war -- neither Iran nor the United States is deeply concerned with which.
Threats to a Resolution
There are two threats to a potential resolution. The primary threat is domestic. In both countries, even talking to each other seems treasonous to some. In Iran, economic problems and exhaustion with grandiosity opens a door. In the United States right now, war is out of the question. And that paves the way to deals unthinkable a few years ago.
A second threat is outside interference. Israel comes to mind, though for Israel, the removal of the nuclear program would give them something they were unable to achieve themselves. The Israelis argued that the Iranian bomb was an existential threat to Israel. But the Israelis lack the military power to deal with it themselves, and they could not force the Americans into action. This is the best deal they can get if they actually feared an Iranian bomb. Though Israel's influence on this negotiation with Iran will face limits with the U.S. administration, Israel will make an effort to insert itself in the process and push its own demands on what constitutes an acceptable Iranian concession.
Saudi Arabia meanwhile will be appalled at a U.S.-Iranian deal. Hostility toward Iran locked the United States into place in support of the Saudis. But the United States is now flush with oil, and Saudi attempts to block reconciliation will not meet a warm reception. The influence of Saudi Arabia in Washington has waned considerably since the Iraq war.
The Russian position will be more interesting. On the surface, the Russians have been effective in Syria. But that's only on the surface. The al Assad regime wasn't bombed, but it remains crippled. And the Syrian crisis revealed a reality the Russians didn't like: If Obama had decided to attack Syria, there was nothing the Russians could have done about it. They have taken a weak hand and played it as cleverly as possible. But it is still a weak hand. The Russians would have liked having the United States bogged down containing Iran's influence, but that isn't going to happen, and the Russians realize that ultimately they lack the weight to make it happen. Syria was a tactical victory for them; Iran would be a strategic defeat.
The Iranian and American realities argue for a settlement. The psyche of both countries is in the balance. There is clearly resistance in both, yet it does not seem strong enough or focused enough to block it. That would seem to indicate speed rather than caution. But of course, getting it done before anyone notices isn't possible. And so much can go wrong here that all of this could become moot. But given how the Iranians and Americans see their positions, the odds are, that something will happen. In my book, The Next Decade, I argued that in the long run Iran and the United States have aligning interests and that an informal alliance is likely in the long run. This isn't the long run yet, and the road will be bumpy, but the logic is there.
