Editor’s Note: Michael D’Antonio is the author of the book “Never Enough: Donald Trump and the Pursuit of Success” and co-author with Peter Eisner of “The Shadow President: The Truth About Mike Pence.” The opinions expressed in this commentary are those of the author. View more opinion articles on CNN.

CNN  — 

The whistleblower who prompted the impeachment inquiry into President Donald Trump said the transcript of a call between the American and Ukrainian presidents had been removed from ordinary document storage and placed in “a separate electronic system that is otherwise used to store and handle classified information of an especially sensitive nature.”

That call is famously controversial since Trump had asked Volodymyr Zelensky to investigate former Vice President Joe Biden and his son and do him the political “favor” of looking into the unsubstantiated theory that Ukraine was in possession of the Democratic National Committee’s hacked email server.

Ultimately, the Trump administration’s decision to hide the record of the call between Zelensky and Trump may prove to be more damaging than the original offense of Trump asking Zelensky to conduct these investigations. The whistleblower’s disclosure raises the logical question: What sort of other communications with world leaders has the Trump administration hidden – in this system or elsewhere? And does anything connect them?

Last Friday, the public got one answer when CNN reported the White House also took steps to limit the access of Trump’s calls with Russian President Vladimir Putin and Saudi Crown Prince Mohammed bin Salman. (Salman goes by the initials MBS.) Putin recently said that Moscow asked the White House to make public the conversation that took place at the 2018 Helsinki summit. But that’s one instance. What about the others?

After the news of hidden calls with Putin and MBS, came news of a Trump call with Australian Prime Minister Scott Morrison in which he again sought personal political favors and, The New York Times reported, the transcript was kept out of the usual distribution system.

The New York Times reported that the “ask” in the Morrison call related to Trump’s persistent effort to somehow prove – against a vast trove of evidence – that he wasn’t aided by Russia in the 2016 election. He wanted Morrison to put Australian resources behind Attorney General William Barr’s effort to review the origins of Robert Mueller’s investigation.

There is so much wrong with all of Trump’s dialing-for-favors that his outreach to Morrison and his use of the attorney general for political purpose, may one day seem like lesser transgressions. Far more significant is the mystery of Trump’s calls with Putin and MBS. Both men have allegedly been involved in lethal activities contrary to American interests and both run countries where Trump and his family have business history.

As MBS admitted on the CBS news program “60 Minutes,” he bears responsibility for the tragedy of the killing of American-based journalist Jamal Khashoggi at a Saudi consulate in Istanbul, but he denies personally ordering the killing.

The killing was blamed on a 15-man Saudi hit squad that referred to Khashoggi as a “sacrificial animal.” After he was dead, Khashoggi’s body was allegedly dismembered and disposed of. It has not been found.

MBS claims the complex and substantial effort to kill Khashoggi and hide the evidence was a rogue operation. The CIA has concluded otherwise.

As a leading and frequent critic of the Saudi regime, Khashoggi was a nuisance to MBS.

Even as MBS accepts “responsibility” for the tragedy, the stain created by Khashoggi’s murder has faded, in large measure because the President of the United States has accepted Prince Salman’s denial of being personally involved and US/Saudi relations appear unchanged.

Trump’s attitude may be credited to the world’s dependence on Saudi oil, which keeps economies humming, and also personal relationships with powerful figures in the kingdom. Prior to the presidency, Trump did tens of millions of dollars in business with Saudis and since his election they have spent lavishly at Trump hotels.

Trump famously made Riyadh a stop on his first foreign trip and he has since catered to the regime. Also, Saudis are a major source of funds invested in a massive real estate development being built by the family of his son-in-law Jared Kushner.

Despite no previous relevant experience, Kushner was brought into the Trump administration and was given a broad portfolio that included the Middle East. He developed a close relationship with Prince Mohammed bin Salman, speaking informally with him often in calls kept secret from other US officials. According to The New York Times, citing people familiar with the matter, Kushner became “the prince’s most important defender” after Khashoggi was murdered.

Just as blood and money mingle in the relationship between Trump administration officials and MBS, they seem to be key factors in the Ukraine scandal. Here the background includes the Trump family’s long-running effort to build a huge real estate project in Moscow.

No one should assume that this interest has abated, or that it doesn’t figure into the Trump/Putin relationship. In this case, the money is a matter of speculation but the blood on Putin’s hands is real. Some 13,000 have died in Ukraine’s war against Russian-backed militant forces favoring Moscow. The dead include 298 people aboard a Malaysian airliner downed by a Russian-made missile. Russia has denied any involvement in the incident.

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    Russia’s interference in Ukraine has been widely condemned, but Donald Trump has reliably cozied-up to Putin. No full explanation has ever been offered for his affectionate relationship with the Russian autocrat, but it falls in line with his positive regard for similarly brutal leaders such as Kim Jong Un of North Korea and Rodrigo Duterte, both of whom reign with murderous terror.

    Although Duterte and Kim have both enjoyed private communications with President Trump, they have not emerged as participants in conversations that have been sequestered in order to protect Trump from embarrassment or worse. While it’s unknown whether or not the White House has kept other conversations with foreign leaders locked up in the same system that was used for the transcript of Trump’s talk with Zelensky, the scandal is young and members of Congress may become intensely interested in what lurks in this seemingly secret venue. Given what’s known thus far, it’s likely that what may emerge will embarrass the President and alarm the world.