(Bloomberg Opinion) -- Prevarication has long been the politician’s stock-in-trade, but President Donald Trump’s attempt to have it both ways over the disappearance of journalist Jamal Khashoggi is no longer tenable.

He has promised “severe punishment” if the government of Saudi Arabia is found to have harmed the Washington Post columnist. But he has expressed reluctance to press harder for fear of losing Saudi defense contracts and the American jobs they sustain. He has called the Saudi king to seek answers, but rather than wait for a full investigation into the mystery, he has chosen to float a conspiracy theory about “rogue killers.”  

While Trump tries to have it both ways, others are taking a stand. A number of prominent American businessmen, including JPMorgan Chase & Co.’s Jamie Dimon and Ford Motor Co.'s Bill Ford, have withdrawn from the Future Investment Initiative, a gathering in Riyadh hosted by Crown Prince Mohammed bin Salman.

Companies like BlackRock Inc. and Siemens AG, whose leaders are slated to attend, have said they are “monitoring the situation,” suggesting they have some anxiety over the reputational risk they incur by associating with the prince, who is better known by his initials MBS.

Global media firms, among them CNN, the New York Times, Nikkei, the Financial Times, and Bloomberg, have pulled out of the event as media partners. Treasury Secretary Steve Mnuchin hasn't yet canceled, but the optics of his attendance won't flatter the Trump administration.

In Washington, too, the voices demanding answers from Riyadh about what happened to Khashoggi have grown to a crescendo. A bipartisan group of senior senators has called on the president to order an investigation, invoking the Magnitsky Act, which can be used to sanction human-rights violators. Senator Rand Paul has threatened a vote to suspend arms supplies to the kingdom. Trump’s own contention that U.S.-Saudi relations are “excellent” is looking more and more like the minority view. And his personal fondness for MBS seems badly misplaced.

The American president can stop equivocating and worrying about Saudi retaliation. In the U.S.-Saudi relationship, the leverage is almost entirely on the American side. It’s Trump’s to use.

His decision to send Secretary of State Mike Pompeo to Riyadh provides the opportunity for some plain speaking with MBS and his father, King Salman bin Abdulaziz asl-Saud. Trump has thus far relied on his son-in-law, Jared Kushner, as his main liason with the crown prince: this has yielded little of substance.

Pompeo could start by giving the king credit for ordering the Saudi public prosecutor to begin an internal investigation, and encourage him to put his personal prestige behind a speedy, transparent investigation. He could extract a promise that the perpetrators will be held to account, even if they turn out to be members of King Salman’s government – or, indeed, of his family.

To show he means business, Trump could also order Mnuchin to call off his trip to the event dubbed the “Davos in the desert.” He might also consider sending some of the senators who have invoked the Magnitsky Act.

The Saudis have suggested they will retaliate against any sanctions. This is mostly bluff. Trump knows that the leverage in the U.S.-Saudi relationship lies mainly on the American side: as he himself put it recently, King Salman wouldn’t last “two weeks” without U.S. support. A more tangible measure of the leverage the U.S. enjoys over Saudi Arabia is that even Trump’s vague threat of punishment was enough to send stocks tumbling on the Riyadh exchange on Sunday.

And what of those defense contracts? Trump can't possibly believe his own contention that the Saudis might, if offended by the U.S., turn to Russia or China. This would be technically impractical. The Saudi military has generations of American weapons which won’t easily be integrated with equipment from other suppliers. More to the point, it would be politically impossible: the Saudis can't risk stepping away from the American protective military and diplomatic umbrella, especially when the country is fighting a hot war in Yemen and a cold one against Iran.

If Trump needs any further proof that he can be tough with Saudi Arabia, he need only look at his own recent success with another ally given to intransigence: Turkey. The hardball tactics that helped bring home pastor Andrew Brunson can also being justice for Jamal Khashoggi. 

To contact the author of this story: Bobby Ghosh at aghosh73@bloomberg.net

To contact the editor responsible for this story: Edward Evans at eevans3@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Bobby Ghosh is a columnist and member of the Bloomberg Opinion editorial board. He writes on foreign affairs, with a special focus on the Middle East and the wider Islamic world.

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