▁to ▁rely ▁extens ively ▁on ▁bal ancing ▁as ▁an ▁efficient ▁power - check ing ▁method ▁due ▁to ▁collect ive ▁action ▁issues . ▁According ▁to ▁him , ▁when ▁a ▁great ▁power ▁finds ▁itself ▁in ▁a ▁def ensive ▁post ure ▁trying ▁to ▁prevent ▁riv als ▁from ▁gain ing ▁power ▁at ▁its ▁exp ense , ▁it ▁can ▁choose ▁to ▁eng age ▁in ▁bal ancing ▁or ▁interven e ▁by ▁favor ing ▁ ▁bu ck - pass ing — trans fer ring ▁the ▁responsibility ▁to ▁act ▁onto ▁other ▁states ▁while ▁remaining ▁on ▁the ▁s idel ines . ▁ ▁In ▁order ▁to ▁determine ▁the ▁circumstances ▁in ▁which ▁great ▁powers ▁behave ▁according ▁to ▁one ▁or ▁the ▁other , ▁M ear she imer ▁builds ▁on ▁W alt z ' s ▁def ensive ▁ne ore al ism ▁by ▁including ▁a ▁second ▁variable — ge ography — al ong side ▁the ▁distribution ▁of ▁power . ▁On ▁one ▁hand , ▁the ▁choice ▁between ▁bal ancing ▁and ▁bu ck - pass ing ▁depends ▁on ▁whether ▁the ▁an arch ic ▁international ▁system ▁is ▁of ▁a ▁b ip olar , ▁bal anced , ▁or ▁un bal anced ▁multip olar ▁architecture . ▁On ▁another ▁hand , ▁state ▁ge ographic ▁location ▁in ▁terms ▁of ▁border ▁sharing ▁and ▁stopping ▁power ▁of ▁water ▁also ▁influ ences ▁great ▁powers ' ▁strategy ▁preference . ▁Com b ined ▁together , ▁these ▁two ▁variables ▁allow ▁him ▁to ▁establish ▁that ▁great ▁powers ▁tend ▁to ▁favor — to ▁the ▁contrary ▁of ▁def ensive ▁ne ore al ism ▁predictions — bu ck - pass ing ▁over ▁bal ancing