(Bloomberg Opinion) -- "There was no collusion. There was no obstruction. I mean, unless you call obstruction the fact that I fight back -- I do fight back, I really fight back. I mean, if you call that obstruction, that's fine." -- Donald Trump, press conference, September 27, 2018Sometimes the president of the United States just shows his hand. He reveals himself in press conferences and interviews and, of course, on Twitter.Yes, these things always feature a lot of word salad and free association that requires everyone around Donald Trump to unpack their magic decoder rings to decipher what he's saying. But there's occasionally a certain there there, especially when it comes to the president's particular fixations -- like Special Counsel Robert Mueller's investigation of possible collusion and obstruction of justice involving Russia and Trump's 2016 presidential campaign.On Thursday morning -- just a week after firing his attorney general, Jeff Sessions, and temporarily replaced him with an apparatchik, Matthew Whitaker -- Trump launched four broadsides at Mueller on Twitter:

That's a lot to chew on, but it boils down to the president saying two things:

  1. "I'm worried."
  2. "I think there are more indictments coming and I'm trying to smear Bob Mueller’s reputation before they land -- but don’t call that obstruction."

A judicious, sophisticated and anxiety-free person wouldn't be playing with fire like this. We already know, based on reporting from Michael Schmidt and Maggie Haberman at the New York Times, that Mueller is looking at Trump's past criticisms of Sessions and former FBI director James Comey on Twitter for evidence of possible obstruction. As my Bloomberg Opinion colleague Noah Feldman has also noted in a column about Trump's tweets, obstruction in this case is defined by two elements: "corrupt intent," or illicitly serving your own interests rather than simply doing your job; and actions that seek to hinder or delay governmental proceedings.

"Trump is free to say what he wants politically," Feldman observed. "He is not free to use his words to try to pervert the course of justice."Such circumstances might recommend playing it cool for a while. "Tread lightly, POTUS," however, isn't advice that fares well in the White House (or at any time in Trump's life, for that matter). In fact, Trump under pressure (think back to how he unproductively lashed out at his bankers when he owed them billions of dollars and almost went broke in the early 1990s) or Trump cornered (think back to his public cage match with a New York mayor whose help he needed to develop a prized project in the 1980s) is never a Trump who keeps calm and carries on. Trump pressured and Trump cornered is a Trump who either self-immolates or morphs into The Kraken, all in the guise of "fighting back."To complicate things, Trump has never before had someone as formidable as Mueller on his tail. He also hasn't confronted an institution as determined to scrutinize him as the House of Representatives will in January. The pressure is incredibly intense – even if Mueller doesn’t directly implicate Trump and the House ends up being feckless. Donald Trump has been running scared for weeks. He was running scared as Election Day neared, uncorking paranoia and racism in an attempt to turn the tide of the campaign. The Democrat’s triumph in the House may have given another leader pause, suggest that it was time for a strategic reset. But a Trump under this much pressure does not cave. Survival is one of the president's lifelong and paramount skills, a central point of pride. So instead, the reclusive, resentful Trump ran roughshod over World War I commemoration ceremonies last weekend in Europe.Behind the scenes he is, as the Los Angeles Times's Eli Stokels tell us, so "furious" about the current course of events that most of his "staffers are trying to avoid him." Senior White House staffers are also uncertain whether their mercurial boss will even let many of them keep their jobs.White House chaos is not a new thing. Trump ran the Trump Organization chaotically and he has run the White House like a tilt-a-whirl since his inauguration. It’s been clear since last year that chaos -- not good management, not deft dealmaking, not strategic dexterity -- was destined to become a defining characteristic of his administration. Few experienced staffers remain to contain it.All along, Mueller has remained a primary force in shaping the president's moods and public posture. The Trump whom New Yorkers have known for decades has now become known nationally by virtue of his inability to avoid confrontation and avoid showing his hand. Trump may not be overly concerned if Muller indicts longtime cronies like Roger Stone. But if he moves, say, to indict his son, Donald Trump Jr., then epic, serial confrontations will be afoot -- and it is likely to end badly for everyone involved. In the meantime, Trump is in the bunker, playing defense.

To contact the author of this story: Timothy L. O'Brien at tobrien46@bloomberg.net

To contact the editor responsible for this story: Mike Nizza at mnizza3@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Timothy L. O’Brien is the executive editor of Bloomberg Opinion. He has been an editor and writer for the New York Times, the Wall Street Journal, HuffPost and Talk magazine. His books include “TrumpNation: The Art of Being The Donald.”

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