A technical paper from the RAND Corporation says publicly available information can make terrorists' job much easier.
Using the U.S. Army's modified intelligence preparation of the battlefield (ModIPB), a red-team of analysts—those who role-play the job of the terrorists—were able to find information making it easier to carry out a terrorist attack against air, rail, and sea infrastructure targets.
The ModIPB framework is a useful guide to locating information relevant to the planning and execution of terrorist attacks.... As a whole, our findings demonstrate that the ModIPB framework performed well as a guide to helping red-team members locate information relevant to the attack. Relying on the checklists we provided, red-team members were able to identify information that, with scattered exceptions, proved useful for planning the hypothetical terrorist attacks across all six scenarios. This assertion is supported by the results of three validation exercises.
Not all information, naturally, is easy to find.
Members of the red team found information concerning the location of terrorist targets, interior structural details, and the size and capacity of security forces relatively easily, but locating information concerning specific security procedures and capabilities was more difficult.
The authors suggest that infrastructure owners continually review and revise operational and informational security activities as new information is constantly becoming available as well as new technology that makes it easier to search and fuse such information together.
To read the shorter summary of the study's findings, click here.