By Michael J. Casey and Paul Vigna

The dot-com bubble of the 1990s is popularly viewed as a period of crazy excess that ended with hundreds of billions of dollars of wealth being destroyed. What’s less often discussed is how all the cheap capital of the boom years helped fund the infrastructure upon which the most important internet innovations would be built after the bubble burst. It paid for the rollout of fiber-optic cable, R&D in 3G networks, and the buildout of giant server farms. All of this would make possible the technologies that are now the bedrock of the world’s most powerful companies: algorithmic search, social media, mobile computing, cloud services, big-data analytics, AI, and more.