This week, Gordon Sondland, the U.S. ambassador to the European Union, found himself giving testimony to the impeachment inquiry in the House of Representatives. He explained in considerable detail how he had come to play an intimate role in the Trump administration’s efforts to leverage U.S. relations with Ukraine to the private advantage of President Trump. Sondland played a central role in executing this corrupt quid pro quo, a strange assignment for anyone — but made all the stranger by the fact that, until a little more than a year ago, Sondland, the founder and chairman of Provenance Hotels, had zero experience as a diplomat.

Ukraine is not a member of the E.U., so there was no jurisdictional reason for Sondland to be involved in U.S. policy toward Ukraine. (In my five years in government during the Obama administration, I participated in many meetings and deliberations concerning Ukraine; I do not recall the U.S. ambassador to the E.U. ever being involved.)

Nor, to judge by the available sources, does Ambassador Sondland have any expertise in Ukraine, Ukrainian, Russia, deterrence theory, European security or diplomacy. Yet there is one very clear reason why Sondland became a member of the Trump foreign policy team: He contributed $1 million to a Trump inauguration party. That’s it. No other reason. Another quid pro quo of the simplest kind: private resources for a public office.

Trump and his closest associates knew that their deal to pressure Ukrainian President Volodymyr Zelensky in return for information politically advantageous to Trump was inappropriate. That’s why they tried to hide the rough transcript of the Trump-Zelensky phone call on the most classified server at the National Security Council.

The dubious nature of this transaction may have something to do with why they enlisted Sondland to help them make this deal. As someone with no previous diplomatic experience, little to no knowledge about the subject matter and completely dependent on Trump for his new ambassadorial position, Sondland was the perfect teammate for Rudolph W. Giuliani and his private lieutenants, who had been deputized by Trump to dig for dirt on the Bidens in Ukraine. (Four of Giuliani’s associates have now been arrested.)

The contrast in behavior between the political appointees and the career ambassadors in executing this operation could not be more striking. Experienced career ambassadors Marie Yovanovitch and William Taylor wanted no part of it. Yovanovitch was fired for trying to stop it. In text messages published after Kurt Volker’s testimony, Taylor called the quid pro quo “crazy.” Sondland, on the other hand, tried to facilitate its execution.

Sondland is not the first unqualified donor to have bought an ambassadorship. Democratic and Republican presidents have both engaged in this selling of diplomatic posts in exchange for campaign contributions. But this embarrassing, wrongful and maybe even illegal involvement of Sondland in a plot to leverage public office for private gain should provide an impetus for putting an end to the practice.

We do not give commands in the military to business people just because they contributed to presidential campaigns. Presidents do not appoint donors to positions at the National Science Foundation or the National Institutes of Health. So why do we treat diplomacy differently — as some kind of novice profession that anyone can do, as long as they are rich? We are the only country in the world that rewards campaign donors with ambassadorships.

To be sure, some donors appointed as ambassadors have served the United States with honor, distinction and creativity. I know many of these terrific people — Democrats and Republicans — and I thank them for their service. But for every excellent donor-turned-diplomat, there are many more who have been out of their depth of expertise, both regarding the country in which they served and the art of diplomacy. One of them may have just helped to get the president of the United States impeached.

Not all career State Department officers make for outstanding ambassadors. Many end up serving in countries in which they don’t know the language, culture or history. And career ambassadors with no connection to the president, the White House or the top political appointees at the State Department are less effective than those who have these relationships.

Presidents should get to choose their own national security teams, including important ambassadorial posts, as a way to change policy. After presidential elections, the infusion of new foreign policy experts with fresh ideas and ties to the new president is an important feature of our democracy. Elections should have consequences even for the conduct of American foreign policy.

The remedy, therefore, is simple: Appoint a greater number of career Foreign Service officers as ambassadors mixed with a smaller proportion of political appointees — all of whom, however, should be chosen for their expertise and not the size of their campaign contributions.

Sen. Elizabeth Warren (D-Mass.) already has announced her plans for such a reform. All other candidates in the 2020 presidential election, both Democrats and Republicans, should make a similar pledge now. Especially in the wake of the Trump-Ukraine scandal, we desperately need to make this change — for the sake of our diplomacy, our national security and our reputation in the world.

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