If you build it, they will come. And attack. Earlier this year, I was brainstorming with Greg Martin, the founder and chief technical officer of ThreatStream, a Google Ventures-backed security startup, about finding a way to show the global nature of attacks against industrial-control systems used in electrical grids, water systems and manufacturing plants. For obvious reasons, attacks against critical infrastructure are among the biggest concerns in cyber-security. Industrial networks are already under daily assault by hackers, and that threat is only growing as more countries develop advanced cyber-war capabilities. Few have been as thoroughly revealed to the public as the United States’ through the disclosures of former National Security Agency contractor Edward Snowden. Martin and I decided on setting up an online decoy known as a honeypot, which was made to look like an enticing industrial-control computer to hackers.