The negotiation over the Khashoggi case will be extremely difficult. The protagonists are headstrong and dangerous people. The issue could easily escalate.

The Ottoman empire ruled over much of the Arab world. The neo-Ottoman wannabe-Sultan Recep Tayyip Erdogan would like to regain that historic position for Turkey. His main competition in this are the al-Sauds. They have much more money and are strategically aligned with Israel and the United States, while Turkey under Erdogan is more or less isolated. The religious-political element of the competition is represented on one side by the Muslim Brotherhood, 'democratic' Islamists to which Erdogan belongs, and the Wahhabi absolutists on the other side.

There are more tactical aspects to this historic conflict. When the Saudis cut ties with Qatar it was Turkey that sent its military to prevent a Saudi invasion of the tiny but extremely rich country. This gave Erdogan the financial backing he urgently needs. In response to that the Saudis offered several $100 millions to prop up the YPK/PKK proxy force the U.S. uses to occupy north-east Syria. These Kurdish groups fight a guerrilla war within Turkey and are a threat to its unity.

The effective Saudi ruler, clown prince Mohammad bin Salman (MbS), made a huge mistake when he ordered the abduction (or murder) of the Saudi journalist Khashoggi in Istanbul. The botched operation gave Erdogan a tool to cut the Saudis to size.

But he needs U.S. support to achieve that. The recent release of the U.S. pastor (and CIA asset) Andrew Brunson is supposed to buy him good will with U.S. President Donald Trump. But Trump build his Middle East policy on his Saudi relations. He can not go berserk on them. Some solution must be found.

Khashoggi was a rather shady guy. A 'journalist' who was also an operator for Saudi and U.S. intelligence services. He was an early recruit of the Muslim Brotherhood:

Khashoggi’s intellectual interests were shaped in his early 20s when he studied in the United States and was also a passionate member of the Muslim Brotherhood. The brotherhood was a secret underground fraternity that wanted to purge the Arab world of the corruption and autocratic rule it saw as a legacy of Western colonialism.

Khashoggi helped in the U.S./Saudi/Pakistani project to destabilize Afghanistan. He met and interviewed Osama bin Laden in Afghanistan and Sudan. The man with the RPG in the upper left picture is Jamal Khashoggi himself.

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Khashoggi became a protege of the longtime head of Saudi intelligence, Turki Faisal Al-Saud. He was engaged in several 'projects' in Afghanistan, Sudan and Algeria. Khashoggi followed Turki as 'media advisor' when he became ambassador in London and later in Washington DC.

Jamal Khashoggi supported the Muslim Brotherhood during the 'Arab Spring'. This was in line with the Hillary Clinton/Barack Obama supported regime change program for most of the Middle East. After the fall of President Mubarak in Egypt and the election win by the Brotherhood the Saudi rulers feared to be the next in line. They started to finance counter revolutions in Egypt and elsewhere. Under the reign of King Salman and his son the suppression of all aspects of Brotherhood influence intensified. Having lost his protection Khashoggi decided to leave Saudi Arabia:

Friends helped Khashoggi obtain a visa that allowed him to stay in the United States as a permanent resident.

Fred Hiatt, the neo-conservative editor of the Washington Post, hired him. The Post published his columns against the Saudi rulers in English and Arabic.

Recently Khashoggi started a number of projects that reek of preparations for a CIA controlled color-revolution in Saudi Arabia:

Jamal Khashoggi, a prolific writer and commentator, was working quietly with intellectuals, reformists and Islamists to launch a group called Democracy for the Arab World Now. He wanted to set up a media watch organization to keep track of press freedom.

He also planned to launch an economic-focused website to translate international reports into Arabic to bring sobering realities to a population often hungry for real news, not propaganda.

Part of Khashoggi’s approach was to include political Islamists in what he saw as democracy building.
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Khashoggi had incorporated his democracy advocacy group, DAWN, in January in Delaware, said Khaled Saffuri, another friend. .. The project was expected to reach out to journalists and lobby for change, representing both Islamists and liberals, said another friend, Azzam Tamimi, a prominent Palestinian-British activist and TV presenter.
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Tamimi said he and Khashoggi had set up a similar pro-democracy project together in 1992 when they first met. It was called Friends of Democracy in Algeria, he said, and followed the botched elections in Algeria, which the government annulled to avert an imminent Islamist victory.

Khashoggi has an enormous number of friends in Washington DC. Mainstream journalists see him as of one of their own. Like them, they feel, he does not deserve such ghastly fate. The neo-liberals as well as the neo-conservatives liked his 'regime change' Arab Spring support and his efforts against Saudi Arabia. Many people in Congress know him personally. They activated procedures under the Global Magnitsky Human Rights Accountability Act that will lead to sanctions against Saudi figures. Media, banks and well known personalities pulled out of a three-day financial conference in Riyadh dubbed “Davos in the Desert".

Trump is under pressure to 'do something', to punish the Saudis and especially MbS.

But Trumps Middle East policy depends on Saudi Arabia and on Mohammad bin Salman personally. MbS finances the U.S. occupation in Syria. Trump's son in law Jared Kushner build his 'peace plan' for Netanyahoo on Saudi endorsement. The sanctions against Iran can only be sustained if Saudi oil replaces the loss of Iranian output. Trump's 'Make America Great Again' program needs the Saudi demand for U.S. weapons. He also needs the Saudis to avoid utter defeat in Afghanistan. Last but not least Trump will perceive the Kashoogi issue as part of the anti-Trump campaign.

Former CIA director Brennan, an avid anti-Trumper, lobbies to dethrone Mohammad bin Salman over the case:

As someone who worked closely with the Saudis for many years, and who lived and worked as a U.S. official for five years in Saudi Arabia, I am certain that if such an operation occurred inside a Saudi diplomatic mission against a high-profile journalist working for a U.S. newspaper, it would have needed the direct authorization of Saudi Arabia’s top leadership — the crown prince.
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I am confident that U.S. intelligence agencies have the capability to determine, with a high degree of certainty, what happened to Khashoggi. If he is found to be dead at the hands of the Saudi government, his demise cannot go unanswered — by the Trump administration, by Congress or by the world community. Ideally, King Salman would take immediate action against those responsible, but if he doesn’t have the will or the ability, the United States would have to act. That would include immediate sanctions on all Saudis involved; a freeze on U.S. military sales to Saudi Arabia; suspension of all routine intelligence cooperation with Saudi security services; and a U.S.-sponsored U.N. Security Council resolution condemning the murder.

The Saudis know what is coming and they are not without defenses. In response to the sanction threats they released a 'f*** you' statement and openly threaten that any sanctions will be responded to with some 30 painful measures:

Riyadh is the capital of its oil, and touching this would affect oil production before any other vital commodity. It would lead to Saudi Arabia's failure to commit to producing 7.5 million barrels. If the price of oil reaching $80 angered President Trump, no one should rule out the price jumping to $100, or $200, or even double that figure.

An oil barrel may be priced in a different currency, Chinese yuan, perhaps, instead of the dollar. And oil is the most important commodity traded by the dollar today.

All of this will throw the Middle East, the entire Muslim world, into the arms of Iran, which will become closer to Riyadh than Washington.
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The US will also be deprived of the Saudi market which is considered one of the top 20 economies in the world.

These are simple procedures that are part of over 30 others that Riyadh will implement directly, without flinching an eye if sanctions are imposed on it, according to Saudi sources who are close to the decision-makers.

The truth is that if Washington imposes sanctions on Riyadh, it will stab its own economy to death, even though it thinks that it is stabbing only Riyadh!

The measures would also cause serious damage to Saudi Arabia. After they were published the Saudi stock market dropped sharply.

The U.S. dollar depends on the secret deal arranged in 1974 that recycles Saudi petro-dollars into U.S. treasuries. If the al-Sauds start to touch that corner stone of the relation, the U.S. will have to invade and smash their shitty country to smithereens. Mecca and Medina would be given back to the Hashemites now ruling Jordan, the Gulf coast line, which holds the oil and oil industry and is mostly inhabited by Shia, would become a state of its own. Yemen would regain its two northern provinces. The plans to do this have long been drawn.

Some solution must be found. The easiest one is for King Salman to fire his son and to reinstate Muhammad bin Nayef, who MbS had dethroned, as crown prince. Nayef is the CIA's man. But if Salman is unwilling or unable to do this, an excuse must be found for whatever  happened to Khashoggi.

The Saudis asked Erdogan to accept a "joint investigation" of the Khashoggi case. This was a request to come to some solution over the issue. Rumors speak of an opening offer of $5 billion as compensation. The Saudi King dispatched the respected governor of Makkah province, Prince Khalid_bin_Faisal_Al_Saud, to Ankara to arrange a deal. The EU3, UK, France and Germany, urge both sides to use this mechanism.

The process to close the case, if both sides wish to do so, is pretty clear:

In statements [..] President Recep Tayyip Erdogan has stopped short of directly accusing the Saudis. Turkish officials have said their president has held his fire in part because he hopes that Washington will help push Saudi Arabia to acknowledge what happened to Mr. Khashoggi.
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Some of Saudi Arabia’s allies in Washington acknowledge that pressure from the United States could force the kingdom to offer some account of Mr. Khashoggi’s fate — even if it is a modified version that shields the kingdom’s day-to-day ruler, Crown Prince Mohammed, from any responsibility.

Some 'rogue element' of the Saudi state could admit that it killed Khashoggi. MbS would deny any knowledge. But fifteen of his most trusted men, those who were seen in Istanbul, would have to be punished. (How would the rest of his body guard react to that?)

The real problem is that both sides, Erdogan and MbS, are extremely headstrong. For both men the issue is much bigger than the Khashoggi case. The conflict has historic, strategic and very personal dimensions. That makes it difficult to find a deal.

Erdogan knows that he is extremely lucky that MbS committed this stupid act under the nose of his secret service. It gives him a tool to cut the Saudis to size. He will introduce new evidence bit by bit to increase the outrage over the case and the pressure on Saudi Arabia.

MbS on the other side will do his utmost to keep his position. He might even let his father die a sudden death should King Salman decide to fire him. Khashoggi was clearly a danger to the throne. MbS probably feels that he did the right thing and does not deserve any criticism over it. After all, abduction and, if needed, murder of dissidents in foreign countries are a long standing Saudi policy that never caused any serious uproar.

Mohammad bin Salman has one mighty ally that may help him to decrease the noise in Congress and the 'do something' pressure on Trump.

The Zionists already recognize that helping MbS is in their interest:

Khashoggi and the Jewish question

Eran Lerman, the vice president of the Jerusalem Institute for Strategic Studies and a former deputy national security council head, said: “It is certainly not in our interests to see the status of the Saudi government diminished in Washington.”
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Lerman envisions a scenario where Jewish political organizations in Washington – such as the American Jewish Committee, which he once worked for as head of its Israel office – may actually go to Capitol Hill, as they have done in the past, and discreetly lobby for the Saudis, something that could paradoxically bring the two countries even closer together.

None of the protagonists of this geopolitical drama deserve any pity. Erdogan, Trump and MbS are thugs. Khashoggi was a willing tool in the destruction of many lives. Seeing these people at each others throat is highly entertaining.

But the conflict is also dangerous. It could escalate into something much bigger that could be painful for many people. Unfortunately there seems to be no one who could talk sense to these people and get them to bury the case.

While I earlier thought that the case would be settled rather sooner than later, I now expect the conflict to go on for weeks or months while collateral damage will accumulate around it.