▁Soviet ▁IC B M s ▁would ▁improve ▁to ▁the ▁point ▁where ▁it ▁was ▁possible ▁to ▁attack ▁US ▁IC B M s ▁while ▁they ▁were ▁still ▁in ▁their ▁sil os . ▁A ▁number ▁of ▁war f ight ing ▁scenarios ▁suggested ▁that ▁a ▁surprise ▁attack ▁would ▁significantly ▁reduce ▁the ▁US ▁stock p ile ▁and ▁greatly ▁bl unt ▁any ▁counter att ack . ▁In ▁the ▁case ▁of ▁the ▁M X , ▁a ▁single ▁successful ▁strike ▁on ▁a ▁sil o ▁would ▁mean ▁ten ▁war head s ▁would ▁not ▁reach ▁the ▁USS R , ▁making ▁these ▁extremely ▁valuable ▁targets . ▁To ▁ensure ▁such ▁an ▁attack ▁would ▁fail , ▁at ▁least ▁to ▁the ▁point ▁where ▁the ▁Mut ual ▁Ass ured ▁Dest ruction ▁( MA D ) ▁would ▁be ▁maintained , ▁a ▁wide ▁variety ▁of ▁bas ing ▁options ▁were ▁considered ▁that ▁would ▁guarantee ▁the ▁surv ival ▁of ▁at ▁least ▁do z ens ▁of ▁M X ' s . ▁ ▁One ▁way ▁to ▁improve ▁the ▁surv ival ▁of ▁the ▁IC B M ▁force ▁would ▁be ▁to ▁act ively ▁defend ▁it ▁with ▁an ▁AB M ▁system . ▁However , ▁the ▁ 1 9 7 2 ▁AB M ▁treat y ▁greatly ▁limited ▁the ▁number ▁and ▁ge ographical ▁deployment ▁of ▁any ▁AB M , ▁with ▁the ▁aim ▁of ▁prevent ing ▁whole - country ▁protection ▁and ▁thus ▁ens uring ▁M AD . ▁Lo AD S ▁addressed ▁these ▁limitations ▁by ▁being ▁deployed ▁along ▁with ▁the ▁rad ars ▁and ▁eng agement ▁computers ▁needed ▁to ▁make ▁a ▁successful ▁attack ▁at ▁only ▁very ▁short ▁ranges , ▁ ▁or ▁less