In the Second World War, the iconic phrase “loose lips sink ships” summed up the need for keeping information that could be useful to the enemy to only those who need it.

It’s 70 years later. Warfare is asymmetric, terrorism is a legitimate threat, and direct action anarchists and extreme left wing groups use violence in various forms to advance their ends. The social imperative for who needs information has diametrically changed. Targeting is a critical component of an attack, but the nature of those who are targeted has evolved. Corporate executives of firms that support a contentious industry or company in a controversial situation may be at risk and not even know it.

How are people targeted? Here’s an example of someone who knew they were at a high risk of being targeted doing a number of things that were forbidden, expressly for the purposes of protecting him. Where was the information shared? Facebook. Facebook is not to blame – what we choose to share is our business, not theirs. However, on that or any other social networking site there are opportunities for our enemies to identify us and use that information to plan attacks, both physical and cyber.

It is imperative that executives and their staff calculate the threat their company and they face and educate their staff on the actions they and their families should be taking to protect themselves. None of these measures are onerous, but all of them protect against not only this kind of threat but also others that target children; children, especially teenagers, are often the weak spot, figuratively and literally. They share information that can be of use in their own kidnapping or compromise the family – education is the key, and it is a simple process that actually should have little impact on their social agenda.

We have to be careful about the information we share and know who might be looking for it. Facebook and its compatriots (like LinkedIn) aren’t evil, but sometimes using them is folly.