Secretary of State Mike Pompeo made history Tuesday night when he addressed the Republican National Convention, a move that critics say violates a long-standing State Department policy that draws a line between diplomacy and politics.

Pompeo videotaped his brief speech Monday night from the rooftop of the famed King David Hotel in Jerusalem, using striking views of the Old City as a backdrop. By the time the public heard his remarks, he had visited Sudan and already traveled on to Bahrain.

Pompeo used his minutes before the camera to tout the Trump administration’s foreign policy, including its exit from the Iran nuclear deal and support for a peace agreement between Israel and the United Arab Emirates announced earlier this month.

“The primary constitutional function of the national government is ensuring your family — and mine — are safe and enjoy the freedom to live, work, learn and worship as they choose,” he said. “Delivering on this duty to keep us safe and our freedoms intact, this president has led bold initiatives in nearly every corner of the world.”

The State Department said Pompeo’s decision to speak at the RNC was made in his personal capacity and did not involve government resources. But it left many diplomats dumbstruck.

“You can argue that U.S. government resources are not being used,” said a former diplomat, who like others spoke on the condition of anonymity to maintain contacts within the State Department. “But is he not speaking as secretary of state? Is he speaking as Joe Blow? I don’t think so.”

Another former senior official called the decision “very tacky.”

Many of Pompeo’s predecessors maintained a high firewall, though some attended their party’s conventions. No sitting secretary of state, however, has made a speech at one.

“As secretary of state, I am obliged not to participate in any way, shape, fashion or form in parochial, political debates. I have to take no sides in the matter,” Colin Powell said in 2004, when he decided not to attend the RNC while he was secretary of state under George W. Bush.

The tradition stretches back to the aftermath of World War II, when Sen. Arthur Vandenberg, a Republican who chaired the Senate Foreign Relations Committee, asserted that “politics stops at the water’s edge.” That means foreign policy represents all Americans, not any particular faction, and should not be infected by domestic politics.

Pompeo’s speech was taped in Jerusalem apparently in part to highlight the successful foreign policy narrative of normalized relations between the United Arab Emirates and Israel, a recognition popular with President Trump’s base of evangelical voters.

Pompeo, an evangelical Christian, once told an interviewer from the Christian Broadcasting Network that it is “possible” that Trump is like a modern-day Esther, a biblical character who persuaded the king of Persia not to destroy the Jews.

The Trump administration has been strongly supportive of Israel. It moved the U.S. Embassy from Tel Aviv to Jerusalem, one of only a handful of countries that have their embassies there because the city’s status was considered a subject for future negotiations with the Palestinians.

Ronald Neumann, president of the American Academy of Diplomacy, noted that Pompeo is building on the practice of previous presidents running for reelection touting their foreign policy successes.

“I see this as a continuation and a piece of how domestic politics have entered into foreign policy,” he said. “It’s a big step, but it’s not out of nowhere.”

The State Department recently updated its restrictions on mixing politics and diplomacy in a memo from the legal adviser dated Dec. 3, 2019, that Pompeo approved.

“The Department has a long-standing policy of limiting participation in partisan campaigns by its political appointees in recognition of the need for the U.S. Government to speak with one voice on foreign policy matters,” the memo said. “The combination of Department policy and Hatch Act requirements effectively bars you from engaging in partisan political activities while on duty, and, in many circumstances, even when you are off duty.”

Among the restrictions in the memo, first reported by Politico and viewed by The Washington Post, is this statement: “Senate-confirmed Presidential appointees may not even attend a political party convention or convention-related event.”

In an email to employees dated Feb. 18, 2020, Deputy Secretary of State Stephen Biegun said the updated guidance was even more restrictive than what is required by law to protect the institution’s integrity as it argues on behalf of American values overseas. He said it applied to all employees.

“In my case, as a Senate-confirmed Department official, I will be sitting on the sidelines of the political process this year and will not be attending any political events, to include the national conventions,” he said in the memo viewed by The Post.

Some veteran diplomats were aghast that Pompeo would make his videotaped speech after approving the updated guidelines.

Nancy McEldowney, the former dean of the Foreign Service Institute that trains incoming diplomats, said Pompeo had crossed the line “of precedent, propriety and ethics.” She called it a “blatant attempt to use American diplomacy to support Trump’s campaign.”

“As we’ve seen in numerous cases and most acutely in Ukraine, Secretary Pompeo will stoop to almost any low to satisfy Trump’s endless need for praise and sycophancy,” she said. “American diplomats put their lives on the line every single day in support of our diplomacy and national security. When Pompeo violates the ethical norms and nonpartisan standards of his office, he fails the people who work under him.”

The State Department declined to comment beyond an early statement saying Pompeo is addressing the convention “in his personal capacity.”

“No State Department resources will be used,” the statement said. “Staff are not involved in preparing the remarks or in the arrangements for Secretary Pompeo’s appearance. The State Department will not bear any costs in conjunction with this appearance.”

Rep. Joaquin Castro (D-Tex.), vice chairman of the House Foreign Affairs Committee, said Pompeo’s participation in the convention was “a potential violation of federal regulations, U.S. State Department policy, and the Hatch Act.”

“It’s absolutely unacceptable that a sitting U.S. Secretary of State, America’s top diplomat, would use official taxpayer-funded business to participate in a political party convention, particularly after the State Department published guidance that explicitly prohibits such activity,” Castro said in a letter to Biegun, adding that a panel would look into the matter.