2!5. leace resting on the system of deterrence has been said to require approximateparity or bal-ance betveen the forces of the States involved. The view is held thatpariLv ceases to exist if one sjde acquires a "firsL-sbrike capabi_Lity', i.e. the capacity to deliver a nucl-ear strike against the other without risking an ihi^1 A.ahlo ya i-41 T,.t 1.hcqF nnndil-.inne lha crcnFr^r.l fcer is thpt rlcl-errenCe can or may faif. Yet the concept of parity rests on a situation vhich isinherentl,y difficult to evaluate, Each super-Pover ts nuelear arsenal consists of many components of different size, function aJld importance. Since each of these components may be subject to constant technological development on both sides, butnot a1r'rays simultaneous\r, par"ity is a process r^'hose equilibrium must continuously be re-estabfished, Hence, the notion of bals"nce is then, by definition, ahcostunstable" In addition, one carnot ignore the psychological factors in the assessment of mutual d.estruction capabilities. The problens connected withestablishing parity are illustrated by the introduction of the broad.er concelt of-'essenrial equivalence'', vhich allows for aslmmetries in the respecLive strategic arsenals. 297" Perhaps the most severe criticism which cou-Id be addressed tovards a system ofsecurity bascd on the concepL of nuclear deterrence relaLes Lo Lhe probLen of vhat !!/ n" Aron 1 r-4 l\ovember J-ybJ,"lnitialions i la strat6gie atomiquerr, le Monde,p. 3.!,/35/i92Inijlisll Annex Page 10i haoDens if delerrence fails. lt is argued that deLerrence has thus far prevented s world conf-l ict, and consequent]-y that deterrence has \.rorked, Apart .fron the f.r'-. f.At mFhv .,r.hor f.cr'tnr s nf a hisfnrinal .1nlirical and other nature have to be considered in that context, it is a truism ta say that deterrence r.rorks, because LhaL sLaLernenL wi-Ll ho-Id. Lrue only until hisLo.ry disproves it" AL t,he
**Analysis**
The text appears to be discussing the concept of nuclear deterrence and its relationship to international security, specifically focusing on the challenges of maintaining balance and equilibrium in the face of technological advancements and the potential for failure. The language and concepts used suggest a focus on international relations, security, and strategic thinking.

**Category**
Science and Technology, International Relations