Like any other weekday, last Friday I grabbed a cup of coffee and activated my computer to see the latest world news cascade down my Twitter feed. But unlike an average day, Twitter was down. Mild discomfort settled in.  Social media addiction aside, it turns out a huge swath of popular websites — from CNN to Github to Paypal to reddit — were down for users in the eastern part of the U.S. The culprit, as we probably should expect by now, was a massive Distributed Denial of Service attack, and it came in two waves. The second was even more powerful, affecting users on the West Coast as well.  So what’s the lesson we should all learn from this attack? Why securing IoT is a national-security imperative