l+10' one raethod of d.efence wou-Id rely on anti-ballistic missiles (A3Ms). under the19?2 Anti-Ballistic Missil-e Treaty, the Lhited states and the soviet union agreed. tolirit deploynent of ABM systems. since then, the developnent of technologies uponwhich an ABM systen could. be based has not been an area of naJor endeavour,Nevertheless some reseaJ'ch vork, for example on laser and charged particle beamrr'eapons, has been carried. out which nay have applications in ABM technorogy. AteehnoLogicaJ- breakthrough in one of these fields could thus l-ead to arecongid.eration of the decision not to d.evelop ABM systems. 4u. Methods of passive defence (civil defence), such as Bhel-ters and evacuation,coul-d not be effective to the extent of denying unaccept€.b1e damage from a majornuclear attack. This is alaply evident fron the effects of nuclear war described. inchapter IV. )+l-2. Most of the atteDtion is therefore directed. towards the trends in thetechnol-ogical d.evelopnent of nuclear-veapon systems ';hi.ch could affect the risk ofa pre-enptive nuclear strike. The super-powers have concentrated in recenr yearson tievel-opiDg capabilities affecting performance of engines, warhead.s and guidance systems of missiles. As is apparent fron chapter III, significant technologicalprogress has been achieved. Engine developrnents incrude nore efficient solid-p"opelfsnt rocket boosters and rel-atively snal"l- and efficient turbofan and turboJeteagines. The l-atter, coupl-ed with d evel-opnent of modern guidance systens, has enabl-ed. a substantial technica.l improvenent of cruise missil-es. The principal deveropnent in werheads ha.s been to increase the diversity and range in weaponsintended for theatre u6e 60 as to improve battlefierd effectiveness ald enhanceflexibility. The l-evel of precision provi d.ed by guidance systens has aLso increasedsignificantly. This d.evelopment offers the prospect of achieviug a very highrrsingle-slrot ki}1 capability" with Land-based balJ.istic missileg and erlareraccuracy vith SLBMrs. l+13. In eddition to developments in the technology directly related to weapons, advances are occurring in other areas, which have inportant irnplications forstrategic policies. rmprovements in the eapability of the cornmand. control and]\/ 35 / 392 English Annex Page 130 cornmunication systems for the st"ategic nucl-ear forces incLude quicker and mo1.e
**Analysis**
The text appears to be discussing the technological developments and implications of anti-ballistic missiles, nuclear weapons, and strategic policies. It highlights advancements in engine, warhead, and guidance system technologies, as well as the potential impact on the risk of a preemptive nuclear strike. The text also mentions the importance of command, control, and communication systems for strategic nuclear forces. Given the focus on military technology and strategic policy, it is likely that the text is related to the development of weapons systems.

**Category**
Science and technology, International relations