Merck cyberattack's $1.3 billion question: Was it an act of war?

By the time Deb Dellapena arrived for work at Merck & Co.’s 90-acre campus north of Philadelphia, there was a handwritten sign on the door: The computers are down. It was worse than it seemed. Some employees who were already at their desks at Merck offices across the U.S. were greeted by an even more unsettling message when they turned on their PCs.