Dedicated armchair observers of insider Washington political maneuvers make a hobby of reading the tea leaves.  Like the lethal version in "Game of Thrones," nothing happens by chance; there is always an underlying strategy to every decision.

Which begs the question: Why did Mueller decide to bring his investigation to a close now?  Some observers thought it could go on for years — why end it before Trump's term ends?  Why end it at all?

My initial reaction, like others, was that Mueller completed his report because he was finished.  There were no more leads to follow, and so Mueller decided on his own to voluntarily end it.  But on further consideration this seems very naïve.

Mueller and his team of rabid anti-Trumpers had every incentive to keep going indefinitely.  The very existence of the Mueller investigation cast a cloud over the Trump presidency.  Like every other effort from the #NeverTrump Swamp, they were seeking to hamstring Trump at every turn.  Having an ongoing investigation was a valuable weapon in the anti-Trump arsenal.  Why give it up?

The idea that Mueller somehow ran out of things to investigate doesn't hold water.  Mueller and his team knew over a year ago (if not on day one) that there was no Trump/Russia connection.  Mueller could have continued to chum the water by looking into Trump's finances or picked a few other minor players on the Trump team to harass and torture with nighttime SWAT team raids and long stints in solitary confinement.  They spent the last year doing just that.

And crucially, keeping the Mueller Investigation open gave the Swamp denizens in the FBI and CIA a legal rationale to deny access to documents that would uncover their spying on the Trump campaign.  As long as Mueller was working, all those pesky requests from congressional investigators like Devin Nunes could be stonewalled.  The Mueller investigation was the best defense that Swampgate had.

And now, with the Mueller investigation closed, the Swamp is exposed — they no longer have an excuse to avoid revealing documents that could incriminate them.  From that perspective, ending the investigation looks like legal suicide.  Why do it?

It may be that William Barr's arrival signaled an adult in the room.  Finally, an attorney general willing to hold Mueller's feet to the fire.  But I doubt this, as Mueller could have fought back against Barr, or at least held out for another year.  With less than two years left in Trump's term, Mueller's team could hope to run out the clock, thus hiding their own culpability in Swampgate forever.

No, there was some other reason.  My guess is the Horowitz Report.  This may be wishful thinking, but there are whispers that the Horowitz Report will be a very damning document, finally revealing the details of Swampgate — how the Obama administration weaponized the FBI, the CIA, and other intelligence agencies to spy on the Trump campaign and undermine the Trump Presidency with a made-up Russia narrative.

If so, the Horowitz Report would destroy Mueller's credibility and that of the Russia investigation once and for all.  And knowing it was about to drop would give Mueller every incentive to finish up his own report and get it out fast before the proverbial s--- hit the fan.  Realizing his time is now limited, Mueller raced to publish his report now, while still unsullied by other charges.

Wishful thinking?  Or reading too much into mere tea leaves?  Only time will tell, once we see what's in the Horowitz Report.

Jay Latimer is an international businessman, writer, and investor who has worked in investment banking in New York, Hong Kong, and Beijing.