President Trump's Twitter feed this week is a jumble of transcribed Fox News quotes, campaign endorsements, positive affirmations of economic data, and bizarre or false, often vitriolic attacks on the media, tech companies, and various members of the law enforcement community. What's going on? Three theories:

1. Trump's agitated about the Russia investigation: "The president's tweetstorm late this week reflects a certain agitation with the news swirling around him, according to people close to Trump, including a growing anxiety within the White House about the possibility of the 'I-word,'" impeachment, Ashely Parker reports at The Washington Post. Those tweets focus on the "Rigged Russia Witch Hunt" by Special Counsel Robert Mueller and various other Justice Department and FBI officials who, as The Atlantic's Natasha Bertrand points out, all have "extensive experience in probing money laundering and organized crime, particularly as they pertain to Russia."

2. Trump wants to reclaim the spotlight from McCain: As the late Sen. John McCain (R-Ariz.) was being eulogized on Thursday, "Trump aggressively tried to wrestle back the attention," tweeting about his 2016 victory, "fake news" — anything but McCain, Katie Rogers says at The New York Times. When McCain's body arrived in Washington, Trump was at a rally in Indiana, and when McCain is being celebrated by "virtually all of official Washington," Rogers and Michael Shear report, "Trump is expected to have retreated to Camp David, where White House aides hope he will contain his anger at the attention being lavished on Mr. McCain."

3. He's sprinting toward authoritarianism: Trump's tweets, Parker says, "are bound by one unifying theme: All of his perceived opponents are peddling false facts and only Trump can be trusted." NYU history professor Ruth Ben-Ghiat says claiming to "the only arbiter of truth" is the hallmark of "an authoritarian in the making or an authoritarian wannabe. ... When Donald Trump is starting to raise the specter of trying to fiddle with search engines and saying that they are rigged — this raises alarm bells in me as a scholar of authoritarianism." Peter Weber