President Donald Trump may be harming America’s foreign policy with one simple — yet often overlooked — move: denying his own team access to notes and information from his meetings with world leaders.

On Sunday, the Washington Post reported that Trump told his interpreter not to tell other US officials what took place during a 2017 meeting with Russian President Vladimir Putin, and seized his notes. The president has apparently not shared records with US officials of other meetings with the Russian leader.

“US officials said there is no detailed record, even in classified files, of Trump’s face-to-face interactions with the Russian leader at five locations over the past two years,” the Post reported.

The White House denies this and other reports, at one point calling the Washington Post piece “outrageously inaccurate.” But if it’s true, it’s quite a problem — and not just because of the possibility of collusion between the two men.

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It actively hurts US officials not to receive a fully detailed briefing about what the president discussed with another head of state. Without knowing what they agreed to, fought about, or even laughed at, it’s nearly impossible for the administration to conduct policy accordingly.

In this case, it seems the US government is devising its policy toward Russia — a nuclear-armed country with designs to sow discord among and within Western nations — while partially blind. “Without knowing what Trump might have agreed with Putin, how can the US government follow up?” Steven Pifer, a former top diplomat who focused on US relations with Russia, told me.

Why record keeping is important to US foreign policy

Slate’s Fred Kaplan noted on Monday that presidents from Dwight Eisenhower through Bill Clinton (and presumably his next two predecessors, as well) all had notes taken of their important meetings. Many, if not all, of those notes now form part of historical archives for students of US foreign policy to see how the country conducted itself through the decades.

Pifer, who is now at the Brookings Institution in Washington, explained to me why these presidents and US officials deem records of these meetings to be so vital.

First, it helps the US pursue the right policies. In some meetings, the US president will strike a deal with his foreign counterpart. The notetaker — whether it’s an interpreter, a key US official, or someone else designated to take notes — will have a record of what was agreed to.

It’s common for interpreters or notetakers to then do an official readout — or summary — of what transpired in the meeting. And even if the president does have a one-on-one with the foreign leader, usually the president gives an aide a readout of that conversation. Basically, the point is someone who’s not the president typically ends up with a full account of what was said, what was agreed to, and any potential sticking points.

The readout helps lower-level officials work on making an agreement a reality. If there are no notes, however, then the government must rely on the memory of officials who were present to get the intricacies of the accord right.

That’s potentially risky. After all, it’s not guaranteed an aide or even the president will remember nitty-gritty details of a meeting after many hours of talks. That could lead the US to pursue goals the foreign leader may have expressly warned against.

And second, detailed records of meetings may capture things that help US officials “gain insights into the other leader’s agenda,” Pifer said. According to the Washington Post, two top Russia policy aides in the Trump administration didn’t get to hear any details from the interpreter after the 2017 Putin meeting in Hamburg, Germany. That hamstrings US foreign policy, since they may have gleaned additional insights from what Putin said had they done so.

“Readouts are especially important for US-Russia meetings,” Pifer told me, “since the US-Russia relationship has needed more guidance from the top than most other US relationships.” He added that during his time in government, Pifer knew of readouts coming out of the US president’s meeting with Soviet and Russian leaders.

The US doesn’t have notes of these meetings. But you can bet the Russians do.

One US official told the Wall Street Journal on Monday that Trump may want to keep details of his talks with Putin secret to stop potential leaks.

But the lack of notes or a good translation of Putin’s comments — let alone the lack of knowledge about what transpired in the meeting — puts the US at a significant disadvantage.

Here’s why: Those who need to know the information in the US government don’t grasp what happened — but Russian officials certainly do.

Trump’s second meeting with Putin, an unplanned encounter during a dinner at the July 2017 G20 meeting in Hamburg, is one case in point. That tête-à-tête included only three people: Trump, Putin, and Putin’s translator.

Russia, then, had a person there to help Putin recount what he discussed with Trump during the hour-long chat; the US can rely only on what Trump recalls. It’s unclear, though, if Trump shared any details of that talk with anyone in the administration.

Why Trump would want to keep his talks with Putin a secret is anyone’s guess. But it’s clear that his desire not to let notetakers inform his administration about America’s discussions with the Russian premier hurts the United States more than it helps.