components may be very closely adapted to each other, but some may have a nul-titr)l-e firnction, connecting rith severaL systems,Al 35/ 392 EnBl:ish A.ruleJa Page !t FIGI'RE IV. EFIECT OF }{IRVINC Before the advent of MIRVed missilesa, preenptive attack by one country-s ICBM force againstthe other country-s ICBltl force would have required theexpenditure 0f at least one of the attacking country-smissi les for each of the attacked country-s missile-silos (top): l,llith a MlRVed missile force, however, onecountry could in principle devote only a fraction of'rrs mlsst tes to an attack against the other-s missiles,expectrng to destroy most if not all of them whileretaining most of its own missiles safe in their sjlos(bottom). In this case it is conceivable some advantagecould. be gained by attacking first. Attacking lllRV-sare snown cross-tarqeted, two to a silo. G-SjE!ti-Lj-!_lrcIi!I!, Nov. I e7e)Al35/392 ts,-rtsn tlnirex ?ase 42 91. There is a continuous evolution of a1I these components - and their lilrl]components - a'hich is too complex to expl-or'e in all its pOssible conbinations. tir'ferent basic principles nay be exploited for sinilar purposes, by thernselves ,.'r.' in conJunction. Different technical soluti.cns fo" particular components nay be combined. in a nuft itude of vays. And, perhaps nost important, each ne'w step may give ri.se to severaL potential countermeasures , which in turn may call for various counter-count er-measures i thus the possibilities roultiply to d.efy cornprehensive rtescriptions, 95. Guid.ance systeurs for vehicles (and for some types of mobile platforms ) are of particular interest, Here it is necessary to distinguish between balllstic nissites, which are guided nainly during the "boosting'i phase, i.e., the initial part of the flight vhen the rocket engines workl vehicles J-ike cruise urissiles' vhieh are driven through the entire flighi; path and for which guidance becoDes navigation; and. weapons (of any kind) in their final- approach to the t€rget, when
**Analysis**
The text appears to be discussing the technological aspects of military systems, specifically the development and deployment of intercontinental ballistic missiles (ICBMs). The language used is technical and complex, indicating a focus on the scientific and engineering aspects of these systems. The text also touches on the strategic implications of these technologies, discussing the potential advantages and disadvantages of certain approaches.

**Category**
Science and technology, Defense