1. Measures taken to reduce the probability of and to minimize the effects of damage caused by hostile action without the intention of taking the initiative. 2. Passive defense minimizes the probability and effects of theater missile attack by reducing an enemy’s ability to target friendly assets, reducing the vulnerability of critical forces and infrastructure, and improving the potential to survive and resume operations after an attack. Passive measures might include counter-surveillance, deception, camouflage and concealment, hardening, electronic warfare, mobility, dispersal, and redundancy. Passive defense is considered one of the four pillars of TMD capability.