Peter Bergen is CNN's national security analyst, a vice president at New America and a professor of practice at Arizona State University. He has been a frequent visitor to Saudi Arabia since 2005.

(CNN) Now that CIA officials have concluded that the murder of Washington Post contributor Jamal Khashoggi was ordered by Saudi Crown Prince Mohammed bin Salman -- an allegation the regime denies -- the crisis in US-Saudi relations has ratcheted up another level.

According to sources cited by CNN and other news organizations, there is sufficient evidence to attribute the orders for the death to bin Salman, also known as MBS.

MBS has also variously presided over a disastrous war in Yemen; the blockade of Saudi Arabia's neighbor, Qatar; the de facto temporary kidnapping of the Lebanese prime minister; and the incarceration in a luxury hotel in the Saudi capital, Riyadh, of some two hundred businessmen and princes, who had to hand over tens of billions to secure their freedom in what the government described as settlements in an anti-corruption drive.

Astonishingly, given the importance of Saudi Arabia there hasn't ever been a Trump-appointed ambassador in the country. The US-Saudi relationship has therefore been largely an informal one managed by President Trump's son-in-law, Jared Kushner, 37, and MBS, 33.

On Tuesday, the Trump administration nominated retired four-star general John Abizaid to be ambassador to Saudi Arabia. The post requires confirmation by the US Senate.

Retired Gen. John Abizaid testifies to the House Oversight and Government Reform Committee in 2007.

What has been sorely lacking is someone of the stature of Abizaid in the Saudi capital to be in regular contact with MBS and to try and provide him some adult supervision.

It's hard to think of someone more qualified than Abizaid for the role. Abizaid, aged 67, speaks fluent Arabic and once ran Central Command (CENTCOM), which is responsible for US military actions in the Middle East. This gives him great expertise and experience in the region as well as the gravitas to speak for President Trump.

Having largely acquiesced in MBS's foolhardy ventures, the Trump administration is beginning to push back a bit. For instance, earlier this month the US ended the American refueling of Saudi warplanes that are bombing Yemen back into the Middle Ages. The administration has also sanctioned 17 Saudis allegedly involved in Khashoggi's murder.

Every day seems to bring some new story of chaos at the White House, not least the defenestration on Wednesday of Deputy National Security Advisor Mira Ricardel because she had angered Melania Trump. That said, the Trump foreign policy team is becoming more professionalized than it was under the hapless Rex Tillerson, who is widely regarded as one of the least successful secretaries of state in American history.

Tillerson had a dismal record of getting qualified diplomats confirmed. By contrast, his successor, Secretary of State Mike Pompeo, has tapped some real stars for significant foreign policy roles.

For Afghanistan, an experienced representative

In addition to Abizaid, another shrewd appointment by the Trump administration was tapping veteran diplomat Zalmay Khalilzad two months ago to be Special Representative to Afghanistan.

Khalilzad is an Afghan American who served as US ambassador to Afghanistan from 2003 to 2005. Khalilzad and the then-Afghan president Hamid Karzai worked closely together at a time when the country was relatively stable. President George W. Bush later appointed him to be ambassador to Iraq and to the United Nations.

He is already leading American discussions with the Taliban to try to produce some kind of peace settlement. That process will surely take time, but it is necessary to bring an end to the conflict in Afghanistan.

Khalilzad may also have the knowledge and experience to bring together the fractious Afghan political establishment to try to ensure a somewhat free and fair presidential election next year.

The previous two presidential elections were both fiascos, marred by widespread fraud. Afghanistan simply cannot afford to have another deeply flawed presidential election, and Khalilzad should use Trump's well-known unpredictability and distaste for the Afghanistan War as leverage to tell Afghan leaders that a presidential election characterized by rampant fraud could result in Trump pulling the plug on American support.

Other capable appointees

Another key appointment by the Trump administration is James F. Jeffrey as Special Representative for Syria Engagement. Jeffrey is an enormously experienced foreign policy official, a Turkish-speaking diplomat who has served as US Ambassador to both of Syria's key neighbors, Iraq and Turkey, and was also Deputy National Security Advisor in George W. Bush's second term.

Jeffrey was one the dozens of signatories of the 'Never Trump' letters by leading Republican national security officials during the 2016 presidential election campaign. In the past, signing such a letter would have torpedoed your chance of serving in a significant role in the administration, but in Jeffrey's case his subject matter expertise has apparently trumped the letter.

Brian Hook, who ran policy planning at the State Department for Tillerson and was widely regarded as one of the few competent officials appointed by Tillerson, was named special envoy for Iran in August.

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The same month, Stephen Biegun , who has had much experience in national security roles on Capitol Hill and at the White House, was appointed special representative for North Korea.

To be sure, Trump himself is so mercurial that even with the appointments of some real heavy hitters to deal with the most challenging foreign policy issues of our time, he can dramatically change his mind on matters relating to any range of countries from Afghanistan to Saudi Arabia.