Richard Clarke has been watching the world for decades. The cybersecurity czar for the Bush and Clinton administrations, Clarke has been thinking and writing about threats – real-world and cyber – for years, culminating in his latest book, Warnings, a forthcoming title co-written with R.P. Eddy.

Warnings looks at seven past Cassandras – people with so-called “sentinel personalities” – who saw the rise of ISIS and the fall of Madoff, and the financial crisis and examines the findings that made them want to warn the world. Then he looks at seven new Cassandras who are warning us about genetic technologies, global warming, and the cybercrime. These seven people are dealing with the seven biggest issues facing the planet today and Clarke and Eddy go in-depth as they explore their warnings.

I talked to Clarke about his book, about sentinel personalities, and about what we can do to stop the worst that’s to come. He’s cautious but, thankfully, hopeful.

Technotopia is a podcast about a better future by John Biggs. You can subscribe in Sticher or iTunes and download the MP3 here.