Megatons of information presented in a vein somewhere between the hardnosed and the smartassed. Canan, a military-affairs reporter for Business Week, sheds few tears for the cause of peace and wastes little time deploring the national-security rationale for arms build-up. What bothers him is the dangerous muddle and waste resulting from almost unchecked competition among the services with their pet contractors, and the inefficacy of the Pentagon's attempts at rationalization. Canan goes through the major kinds of weaponry now being deployed or planned--jet fighters, land-based ICBM systems, ballistic-missile submarines, huge high-speed hydrofoils, electronic infantry equipment, drones (pilotless planes), lasers for multiple uses. Canan's main purpose is not to expose boondoggles and trickery (although there are some horrors like the Air Force general who quietly lowered the specifications for a new fighter plane engine and simply announced that it had passed the tests), but to show the momentum of procedural illogic in action. Thus we see a Navy. and Air Force that resist interservice standardization of weapons, each screaming blue murder at inefficiency or cost overruns by the other's favorite contractor; congressmen who cut arbitrarily chosen amounts from arbitrarily chosen programs while fearlessly defending whatever keeps the local Grumman or McDonnell-Douglas plant in business; a Defense Department whose chaotic, redundant array of commitments reflects an unthinking determination to keep military strategy abreast of technology in every imaginable area. Canan's profoundly depressing study demonstrates with grim clarity that the national investment in defense is inextricably built into (and beyond) the foreseeable future. It's partly sheer size, partly the complementary insanity of the Russians, but mostly the astonishing military philosophy of instant obsolescence which puts the nation at the mercy of research-and-development experts and makes every new zillion-dollar bomb, submarine, or plane ancient history before it's completed. ""As they say at the Pentagon, 'If it has already flown, it is already obsolete.'