Washington: Marie Yovanovitch’s scheduled deposition to the House impeachment inquiry Friday will give congressional investigators an inside look into the growing politicization of State Department diplomacy under President Donald Trump.

Yovanovitch, whom Trump scorned and recalled as ambassador to Ukraine, is an important witness in the probe of the president’s effort to use diplomacy as a personal campaign tool, an allegation he denies.

He apparently didn’t consider her enough of a team player in his plan, which was managed by the president’s personal lawyer Rudy Giuliani, for a politically driven investigation by Kiev into a potential campaign opponent, former vice president Joe Biden and, his son Hunter Biden.

Her recall and Trump’s denunciation incensed Women Ambassadors Serving America (WASA), an organization of over 170 current and former U.S. envoys.

Citing the White House memorandum of Trump’s July 25 call with Ukranian President Volodymyr Zelensky, WASA’s recent statement chided Trump for comments that “demean and threaten Ambassador Yovanovitch . . . despite her very strong record of speaking out clearly and firmly against corruption in Ukraine.”

She had already been recalled from Kiev in May, but that didn’t stop Trump from “denigrating the Ambassador and stating that ‘she’s going to go through some things’ “ during the call, the statement complained.

Trump’s comment “suggests that it might be an intention to punish the Ambassador for unspecified actions,” the statement added.

“This appears to be a threat of retaliation for political reasons, which is both shocking and inappropriate.”

Another former ambassador to Ukraine, Steven Pifer, described Trump’s request to Ukraine for “derogatory information” on Biden as “an abuse of power.”

Pifer’s email added this ominous prospect: “I have seen nothing quite as blatant at this but have to wonder if there are other questions where the White House has subverted American interests to the President’s.”

Earlier this week, the White House blocked the House appearance of Gordon Sondland, the U.S. ambassador to the European Union. The White House said the administration would not participate in the “partisan and unconstitutional inquiry.”

It is Trump’s State Department, however, that has played partisan politics. An August report by the State Department Office of Inspector General said “numerous employees” protested that Assistant Secretary Kevin Moley and his former senior adviser Mari Stull praised or criticized staffers because of their “perceived political views. For example, several career employees reported that throughout her tenure at the Department, Ms. Stull referred to them or to other career employees as ‘Obama holdovers,’ ‘traitors,’ or ‘disloyal.’ “

In one case, Stull accused an employee who had accompanied Congressional Black Caucus members to the United Nations, as is routine, of “trying to ‘thwart’ President Trump and undermine his agenda,” the inspector general reported. “After the trip, many of the employee’s job responsibilities were taken away.”

In a response included with the report, Moley said, “I did not accuse any individual of undermining the President’s agenda.”

Stull left the department and could not be reached for comment.

The office said it could close its recommendation that department officials consider disciplinary action against Moley when the State Department decides on what action, if any, it plans to take. The recommendation remains open.

Holding military assistance to Kiev hostage to Trump’s appeal for a politically driven investigation into a potential election opponent, as reflected in the Trump call with Zelensky, was another example of Trump’s private interest eclipsing the national interest.

Trump says that there was not a quid pro quo and that his call was “perfect.”

In addition, there is a growing belief among State’s workforce, The Washington Post reported Monday, that Secretary of State Mike Pompeo “has subordinated its mission and abandoned colleagues in the service of President Trump’s political aims.”

Before any of this, there was a sharp increase under Trump in political appointees taking positions that could be held by career staffers. About 45 percent of the ambassadors he has appointed are politicos, compared with just 30 percent under the Obama administration, according to the American Foreign Service Association, the union for foreign service officers.

Except for the director general slot that by law must go to a foreign service officer, “there is not a single career official who has been nominated to be assistant secretary of a bureau,” said retired ambassador Laura Kennedy, who was among those signing the WASA statement. “It is unprecedented for the career public servants to be thus shut out of the policy level ranks of the State Department.”