CONFIDENTIAL pee 1756 enim PROBLEM FACTS Weapons systems cost-effectiveness studies indicate high probability now and for the next several years of target penetration by attacking aircraft. At no time do such studies envisage an airtight defensive system. No system now exists capable of attacking and destroying intercontinental ballistic missiles (1cBM). In spite of the fact that passive measures can do much to attenuate the effects of the damage that current and proposed active defense systems must permit, the us has followed a wavering and ineffective passive defense policy that has never won the support of Congress or the public. This study examines passive measures that might be essential ingredients of a balanced passive-active air defense system. DISCUSSION Six urban centers — Washington (studied in detail), Boston, Dayton, Milwaukee, St. Louis, and San Francisco — were chosen as targets, and -the feasibility, effectiveness, and costs of various coursesof preattack civil defense action for these cities were investigated. Feasibility An examination of the capacities of the radial road nets leading out of the target cities indicated that for only one, Dayton, was mass radial evacuation feasible within the most probable warning time that the cities would receive. This was true even though the model did not allow for losses in starting time, panic, failure to follow the plan, vehicle breakdowns, etc. A survey of the national highway program and possible new radial routes to speed evacuation indicated that these roads could not be made available within the time period when mass evacuation maybeeffective (prior to the 1cBM). Thefeasibility of evacuating urban targets to smaller towns and villages was examined, using Washington and Baltimore as targets, and Frederick and Hagerstown, Md., and Fredericksburg, Va., as the host towns. This tactic required many times the most probable warning times expected and had theeffect of creating three new highly concentrated population targets. Legislative apathy and public lack of knowledge of weaponseffects seem to be the principal barriers to shelter programs — technical know-how exists and adequate shelter designs have been built and tested at atomic weapon test sites. ORO-—R-17 (App B) 1 CONFIDENTIAL ay at” aa Assuming some prior warning, to evaluate the feasibility, effectiveness, and costs of several courses of preattack civil defense action: mass evacuation, seeking ordinarily existing shelter, seeking shelter in towns, villages, and farms, and seeking underground public or private shelter.