What did Donald Trump do today?

He pled ignorance of a massive national security scandal that broke today.

Today, journalist and editor Jeffrey Goldberg published a story in The Atlantic detailing how he was accidentally added to a private group chat between Trump administration officials on a commercial messaging service. The subject of the group was the U.S. military strike against the Houthi rebels in Yemen on March 15. 

After being added to the chat by Trump's national security advisor Mike Waltz, Goldberg was able to see detailed information that, "if they had been read by an adversary of the United States, could conceivably have been used to harm American military and intelligence personnel."

The chat included Vice-President J.D. Vance, Secretary of State Marco Rubio, Secretary of Defense Pete Hegseth, Director of National Intelligence Tulsi Gabbard, and a number of other senior intelligence officials appointed by Trump. (The links in the previous sentence go to some of their comments on the importance of protecting classified information.) None of them noticed or questioned Goldberg's presence.

In addition to the leak being embarrassing, the very existence of the group itself is almost certainly illegal. Signal is a private commercial service, and it has not been approved for use by government officials. There are several secure electronic systems that are—but Trump's appointees may have been hesitant to use them because they create records that cannot be deleted without leaving tracks. (Messages in the chat Goldberg saw were set to delete after a period of time, which is illegal as they are government records.)

Gross negligence by government officials in exposing secret defense information is a felony punishable by up to ten years in prison.

Asked about the matter today, several hours after the story broke, Trump said he'd never heard anything about it.

REPORTER: …your reaction to the story in the The Atlantic today that said that some of your top cabinet officials and aides had been discussing very sensitive material on Signal… What is your response to that?

TRUMP: I don't know anything about it. I'm not a big fan of The Atlantic. To me it's a magazine that's going out of business, I think it's not much of a magazine, but I know nothing about it. You're saying that they had—what?

REPORTER: They were using Signal to coordinate on sensitive materials.

TRUMP: Having to do with what? Having to do with what? What were they talking about?

REPORTER: The Houthis.

TRUMP: The Houthis? You mean the attack on the Houthis?

REPORTER: Right.

TRUMP: Well it couldn't have been very effective, because the attack was very effective, I can tell you that. I don't know anything about it. You're—you're telling me about it for the first time.

Goldberg's article makes clear that administration officials were asked for comment before publication, and the article as published includes confirmation from the National Security Council that the Signal thread was genuine. 

If Trump's apparent bewilderment was genuine, it means that he was never told about a massive security breach—or that he was, today, and had already forgotten.

Why does this matter?

• There's no functional difference between a president who is cut out of the loop by his own staff, and one who can't remember what they told him anyway.

• The president is responsible for the incompetence of the people he puts in charge of national security.