I am not certain when Facebook first applied persuasive technology to its design, but I can imagine that the decision was not controversial. Advertisers and media companies had been using similar techniques for decades. Despite complaints about television from educators and psychologists, few people objected strenuously to the persuasive techniques employed by networks and advertisers. Policy makers and the public viewed them as legitimate business tools. On PCs, those tools were no more harmful than on television. Then came smartphones, which changed everything. User count and usage exploded, as did the impact of persuasive technologies, enabling widespread addiction. That is when Facebook ran afoul of the law of unintended consequences. Zuck and his team did not anticipate that the design choices that made Facebook so compelling for users would also enable a wide range of undesirable behaviors. When those behaviors became obvious after the 2016 presidential election, Facebook first denied their existence, then responsibility for them. Perhaps it was a reflexive corporate reaction. In any case, Zuck, Sheryl, the team at Facebook, and the board of directors missed an opportunity to build a new trust with users and policy makers. Those of us who had advised Zuck and profited from Facebook’s success also bear some responsibility for what later transpired. We suffered from a failure of imagination. The notion that massive success by a tech startup could undermine society and democracy did not occur to me or, so far as I know, to anyone in our community. Now the whole world is paying for it.