Editor's note: Gary Sick served on the National Security Council staff under Presidents Gerald Ford, Jimmy Carter and Ronald Reagan, and he was the principal White House aide for Iran during the Iranian Revolution and the hostage crisis. Sick is a senior research scholar and adjunct professor of international affairs at Columbia University, a member of the board of Human Rights Watch in New York and founding chair of its advisory committee on the Middle East and North Africa.
(CNN) -- President Barack Obama is getting a lot of free advice. Here's a question, not an answer: With every issue in the Middle East intertwined with every other, like a giant bowl of spaghetti, where do you begin?
In reality, no matter where you begin in the Middle East, each strand connects to almost every other:
Syria? Immediately you must think of the Turks who are harboring refugees and fighters just across the border, and Syrian Kurds, who are beginning to harbor thoughts of autonomy and are increasing contacts with their ethnic brothers in Iraq and Turkey.
Iran, of course, is aiding the beleaguered Bashar al-Assad but also trying to organize an exit strategy; Saudi Arabia and Qatar are pouring money and arms into the country with the sole purpose of cracking the Syria-Iran entente; Iraq fears that a Sunni takeover in Syria will revitalize its own restless Sunnis.
The Palestinian issue? No need to elaborate. That is tangled up with everything in the Middle East.
The Arab awakening? The policies you adopt with the emerging Islamist governments will affect every strand you touch in the region, from relations with Israel to the Arab states in the Persian Gulf that are terrified of sweeping change.
The president will not have the luxury of choosing a single issue and ignoring or postponing all the others. The whole Middle East has a habit of intruding, and policy choices will have to be made about each of the major issues, even if it is not convenient.
Still, in plotting a second term, the president must establish some priorities. Trying to do everything at once is not only bad strategy, it is a certain recipe for failure across the board.
A point of entry: Possibly the most promising strand to pull when trying to unravel the Mideast problem is the Iranian dilemma. When Obama came into office four years ago, he courageously promised to engage Iranian leaders. He made a genuine attempt, but he quickly pulled back in the face of Iran's brutal suppression of a civil uprising, Israeli demands for an early deadline on the nuclear issue and the fact that he had a lot on his domestic plate. Trita Parsi evocatively describes that episode in the book "A Single Roll of the Dice."
There was no staying power. Instead, the United States reverted to its default position of sanctions while maintaining the framework for serious negotiations with Iran as part of the so-called P5+1 -- the five permanent members of the U.N. Security Council (the United States, Britain, France, China and Russia) plus one (Germany).
The sanctions did their job. Iran has gladly accepted the invitation of the P5+1 to return to the negotiating table. However, in the run-up to the presidential election, the United States was unwilling to put a meaningful offer on the table, and the negotiating track languished in a kind of limbo.
The value of sanctions: Sanctions have two useful purposes. One is to persuade Iran to return to the negotiating table. That has happened. The other is to give the sanctioning party something to bargain away in return for concessions.
Up to this point, the United States has been unwilling to offer significant sanctions relief in return for significant concessions from Iran. Sanctions have assumed a life of their own and are gradually becoming politically untouchable. If that remains true, then there is no prospect of serious negotiations.
There is another use of sanctions -- to punish a party you don't like and potentially coerce them into submission or collapse. The current sanctions regime is taking on that coloration, even if it is seldom discussed as such.
The record of sanctions in producing abject surrender or regime change is not promising. Instead, the sanctions typically hurt the average citizen, while leaders escape most of the effects and adopt a defiant posture, blaming their own failings on outside interference. This is beginning to happen in Iran today.
Vicious assaults on the well-being of a country's population can produce popular bitterness and hostility against the "enemy" that can last for generations.
The shape of an agenda: As with many long-standing disputes, the broad outlines of a settlement are well-known to the parties. What is lacking is the political judgment by both sides that now is the moment to proceed with a deal that will require mutual compromise.
The United States and its allies will have to accept a measure of Iranian domestic enrichment of uranium. Iran will have to accept limits on its entire nuclear infrastructure, subject to intrusive inspections and monitoring. Iran will need to document the history of its nuclear program, and the West will need to remove sanctions. All of this must happen in a step-by-step process with safeguards and verifications at each stage.
There is nothing easy about it. The Iranians are known as obstinate and often infuriating negotiators. The United States is not known for its patience, and it can be clumsy and ponderous as it attempts to please multiple constituencies at the same time. Iran is certain to face strong objections from its hardliners, and the same will apply in the United States.
The hardliners on both sides, who regard another Middle East war as an acceptable option, reinforce each other and impede efforts to find mutually acceptable compromises. Israel and the U.S. Congress will try to impose impractically tight deadlines. And events in the region, such as the recent case of Iranian aircraft firing on a U.S. surveillance drone, can sabotage negotiations.
The Arab states of the Gulf will be intensely suspicious of any hint of a secret deal between the United States and Iran. They remember America's strategic reliance on the shah, the Reagan administration's covert sale of weapons to Iran in the mid-1980s and America's installation of a Shia government in Iraq. They (and Israel) will have to be persuaded that any accommodation with Iran is not at their expense.
Private and public negotiations: The starting point must be private U.S.-Iran discussions, leading to an agreed agenda. Both sides have recently hinted that such talks are under consideration, and reactions from the European Union, Russia and even the American people have been undismayed, even openly supportive.
The choice of representatives and venues is less important than confidence that delegates credibly reflect the view of their leaders. Experience suggests that an agreed agenda is more likely to emerge from bilateral discussions outside the glare of publicity. If that is accomplished, then the actual negotiations could be carried out within the existing P5+1 framework.
Even a preliminary agreement -- establishing a mutually acceptable process with a defined end point -- would help to unravel some of the tangles of Middle East issues.
The threat of a new war in the Middle East would be reduced. The possibility of getting Iranian cooperation on Syria would be improved. The threat of nuclear proliferation in the region would be tamped down at least temporarily. And the multiple flash points in the Gulf could potentially cool down, leaving opportunities for more constructive initiatives.
The history of U.S.-Iran relations is a story of relentless hostility and serial missed opportunities. Chances for genuine progress come along scarcely once in a decade.
So, Mr. President, here is one more piece of free advice: The present constellation of circumstances with Iran is probably the best you're going to get. Don't let it pass.
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The opinions in this commentary are solely those of Gary Sick.