President Trump spoke about the media while at the Celebrate Freedom Concert in Washington D.C. on July 1. (The Washington Post)

President Trump began his Sunday by slamming the media on Twitter before spending the afternoon at one of his golf courses and tuning in to Fox News in the evening. It was a typical weekend day, in other words.

Yet the president's tweets — which did not involve wrestling footage or a plastic surgery-related insult and therefore seemed unremarkable — could foreshadow something more intense and unusual.

Here's what Trump posted, in case you missed it:

A couple of reminders before we move on:

Clinton's campaign was tipped off to a question twice during the Democratic primary, once before a debate and once before a candidate forum, by Donna Brazile, who at the time was a Democratic National Committee member and a CNN analyst. Brazile's leaks were unethical but not illegal, and the disadvantaged candidate was Sen. Bernie Sanders, not Trump.

The Washington Post-ABC News poll has an A-plus rating from FiveThirtyEight and, contrary to the president's claim, came pretty close to predicting the election result. Its final pre-election survey showed Clinton leading, 47 percent to 43 percent; Clinton won the popular vote, 48.2 percent to 46.1 percent.

Complaints about polls and unnamed sources are standard fare from @realDonaldTrump, but the president's team is plotting new, targeted attacks. In a report last week on the White House's response to news about Donald Trump Jr.'s meeting with a Russian lawyer was this nugget from The Post's Philip Rucker and Ashley Parker:

“A handful of Republican operatives close to the White House are scrambling to Trump Jr.’s defense and have begun what could be an extensive campaign to try to discredit some of the journalists who have been reporting on the matter.

Their plan, as one member of the team described it, is to research the reporters’ previous work, in some cases going back years, and to exploit any mistakes or perceived biases. They intend to demand corrections, trumpet errors on social media and feed them to conservative outlets, such as Fox News.”

Recall that April Ryan, a White House correspondent for American Urban Radio Networks, reported in February that a member of the president's communications team threatened her by claiming that Ryan is one of several journalists on whom Trump officials have compiled dossiers of negative information.

“That is absolutely not true,” White House press secretary Sean Spicer said at the next media briefing. “There are no dossiers being kept. It's just a binder that I put right here; that's about it. That was a joke.”

Perhaps it was, but we got a preview of what a dossier on a journalist might look like, during the presidential race, when former Trump campaign manager Corey Lewandowski dug into previous work by Newsweek reporter Kurt Eichenwald and leveled a misleading charge on CNN. Lewandowski, a CNN commentator at the time, claimed that Eichenwald “has said that George W. Bush was directly involved with 9/11. He has no credibility.”

As I wrote then, “Eichenwald was highly critical of Bush's response to intelligence. But he certainly did not accuse the former president of being 'directly involved with 9/11.'”

Lewandowski's attack was prompted by Eichenwald's reporting on potential conflicts of interest presented by the Trump Organization's foreign interests. The strategy was clear: cast aspersions on the journalist's old reporting to make his new reporting appear suspect.

It's not clear if that strategy is in play here, but Trump's accusatory tweets take on a different significance if his team executes on the plan described in The Post's reporting.