...the combatants come from bomb-making terrorist groups like Osama bin Laden's al-Qaeda, or drug smuggling cartels like those in Colombia and Mexico. On the positive side are civil-society activists fighting for the environment, democracy and human rights. What all have in common is that they operate in small, dispersed units that can deploy anywhere, anytime to penetrate and disrupt. They all feature network forms of organization, doctrine, strategy, and technology attuned to the information age. And, from the Intifadah to the drug war, they are proving very hard to beat. Extract from http://www.rand.org/publications/MR/MR1382/ Check out chapter 4,It's a Killer. "Encryption can pose potentially insurmountable challenges to law enforcement when used in conjunction with communication or plans for executing serious terrorist and criminal acts."