I want to make a somewhat serious point about Donald Trump's ridiculous note from his doctor, if that's even possible.

The presidency is a job far too large for any one human being. It requires simultaneous management of everything from the Iranian nuclear deal to hurricane relief efforts to government procurement reform to legislative outreach. No one can keep that much in his head at one time.

For that reason, the most important decision a president makes is in choosing his or her staff. In the end, it's the staff that gives the president the information and counsel necessary to make all the other decisions. In some cases, it's the staff that ends up actually making the decisions. That's why the media routinely talks about the "Obama administration" or the "White House" — it's an admission that a presidency is made up of many, many people.

The best argument for Donald Trump is that he's got a public face and a private face. The public face is his Twitter account, his yuuuge statements, his endless feuds — and it's all cynical, an effort to gin up press coverage, because Trump is the only candidate who has ever run for president truly understanding that there's no such thing as bad publicity.

These are excerpts from Trump's "The Art of the Deal," pub.1987. Feels like an appropriate time to share pic.twitter.com/wwWSobKGze — Sage Boggs (@sageboggs) December 8, 2015

The hope is that, privately, Trump is a calculating businessman who has become a billionaire and global star by making good decisions based on good evidence and surrounding himself with good people.

There are arguments for both sides of this. On the one hand, Trump really is a billionaire. On the other, he might have made more money if he'd just invested his inheritance in the S&P 500. Similarly, Trump's main innovation as a real estate developer was to license his celebrity to other developers — a smart move, perhaps, but not one that suggests a deep well of skills behind making himself better and better known.

It's in light of this argument that things like this doctor's note are worrying. If Trump has seriously entrusted his health to a clown who would write a note like this, what does that say about the kinds of people he surrounds himself with? What does it say about his willingness to have people in his inner circle who tell him things he doesn't want to hear, and who modulate his worst impulses?

Trump's campaign is an embarrassment. His policy proposals are a joke. The saving grace of his candidacy has been the suspicion that he's playing a deeper game — that the offensiveness is calculated, that the proposals aren't serious, that the Donald is more than he appears. But maybe he's not.

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