When self-delusion and self-flattery enter the mind-set of a product team and the metrics they judge themselves by, like the first plague rat coming onto a ship, the end is practically preordained.

In Silicon Valley, where I worked at companies like Facebook and Twitter for the earlier part of this decade, Cuba was generally regarded, when it was regarded at all, as a technological curiosity.

If you'd come to me in 2012, when the last presidential election was raging and we were cooking up ever more complicated ways to monetize Facebook data, and told me that Russian agents in the Kremlin's employ would be buying Facebook ads to subvert American democracy, I'd have asked where your tin-foil hat was.

If democracy is to survive Facebook, that company must realize the outsized role it now plays as both the public forum where our strident democratic drama unfolds and as the vehicle for those who aspire to control that drama's course. Facebook, welcome to the big leagues.