It was a nothing burger of a story, quickly fading, but here's an interesting explanation of what happened

How Goldberg Got Added to the Signal Chat

According to three people briefed on the internal investigation, Goldberg had emailed the campaign about a story that criticized Trump for his attitude towards wounded service members. To push back against the story, the campaign enlisted the help of Waltz, their national security surrogate.

Goldberg’s email was forwarded to then Trump spokesperson Brian Hughes, who then copied and pasted the content of the email – including the signature block with Goldberg’s phone number – into a text message that he sent to Waltz, so that he could be briefed on the forthcoming story.

Waltz did not ultimately call Goldberg, the people said, but in an extraordinary twist, inadvertently ended up saving Goldberg’s number in his iPhone – under the contact card for Hughes, now the spokesperson for the national security council.

According to the White House, the number was erroneously saved during a “contact suggestion update” by Waltz’s iPhone, which one person described as the function where an iPhone algorithm adds a previously unknown number to an existing contact that it detects may be related.

The mistake went unnoticed until last month when Waltz sought to add Hughes to the Signal group chat – but ended up adding Goldberg’s number to the 13 March message chain named “Houthi PC small group”, where several top US officials discussed plans for strikes against the Houthis.

Waltz said in the immediate aftermath of the incident that he had never met or communicated with Goldberg. He also suggested on Fox News that Goldberg’s number had been “sucked” into his phone, seemingly in reference to how his iPhone had saved Goldberg’s number.

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Waltz also appears to have also engendered some sympathy from inside Trump’s orbit over the group chat because the White House had authorized the use of Signal, largely because there is no alternative platform to text in real time across different agencies, two people familiar with the matter said.

Previous administrations, including the Biden White House, did not develop an alternative platform to Signal, one of the people said. As a temporary solution, the Trump White House told officials to use Signal as they had done during the transition instead of regular text-message chains.