There have been several high-profile systemic failures in the past few years that give us a glimpse into the hypothetical you’re describing. Most interruptions have lasted mere hours, if not minutes, before causing mass panic and devastating economic catastrophes. Planes are grounded, banks stop operations, global trade shuts down, and hospitals can’t access patient records.

The question isn’t how long before it would be a huge problem. That starts immediately. The better question is, how long before people adapt to a world without the internet? How long would it take to build an alternative?