In 1982, when I began my career as a technology investor, privacy was not a concern. The denizens of Silicon Valley shared a goal: to improve the lives of the people who used technology. An idealized form of capitalism reigned supreme. IBM had just shipped its PC, and the personal computer was about to take off. Optimism pervaded the nascent industry. Steve Jobs spoke of computers as “bicycles for the mind,” expanding human capabilities with little or no downside.

Over the course of a three-decade-plus career, I have advised countless companies and entrepreneurs, from those early days of personal computers to the current generation of social networks. I was an adviser to Mark Zuckerberg at Facebook from 2006 to 2009, and I helped bring Sheryl Sandberg to that company (I remain a shareholder in the company). Since 2017, I have been raising awareness of the threats to privacy, democracy, public health and innovation from the business models and algorithms of internet platforms.

Privacy did not become a problem until the widespread deployment of networks in the 1990s, and even then the issues were comparatively small. Up until around 2000, the technology industry never had enough processing power, memory, storage or network bandwidth to build products that could be deeply integrated with our lives. Every product required compromises, every design depended on the experience and artistry of its creators.

The bursting of the internet bubble in March 2000 set in motion forces that would alter the culture and priorities of Silicon Valley. The venture capital industry retreated, and in its place arose a new group of investors, known as angels, who typically invest their own personal fortunes in start-ups. Foremost among them was the so-called PayPal Mafia — led by Peter Thiel, Elon Musk and Reid Hoffman — who transformed Silicon Valley with two brilliant insights.