Cyberattacks on connected US infrastructure are a growing threat, and this is bad news for cities that have linked cameras, traffic lights, and other systems together.

• As the US gets more involved in conflicts abroad, retaliation could increasingly come in the form of cyberattacks at home instead of traditional warfare.
• Europe's recent disruptions, including economic problems and spoiled food from system failures, show what can go wrong when infrastructure gets hit.
• The more cities connect things like surveillance cameras and traffic light controllers into shared networks, the bigger the target becomes for hackers.
• A successful attack on these linked systems could cause disruption on a scale the country isn't ready to handle.

Outlook: Expect growing calls to review and secure connected city infrastructure before an attack forces the issue.