▁ 1 9 6 0 s . ▁The ▁" mid - size ▁constitu ency " ▁elect oral ▁system ▁allowed ▁Japan ▁to ▁establish ▁a ▁stable ▁government . ▁The ▁L DP , ▁which ▁aver aged ▁over ▁ 4 0 ▁percent ▁of ▁the ▁vote ▁in ▁the ▁national ▁elections , ▁could ▁retain ▁slightly ▁more ▁than ▁half ▁the ▁seats ▁in ▁the ▁House ▁of ▁Representatives ▁and ▁the ▁House ▁of ▁Coun c ill ors . ▁With ▁this ▁absolute ▁majority ▁of ▁seats ▁in ▁the ▁Diet , ▁the ▁L DP ▁could ▁implement ▁consistent ▁policies ▁effectively , ▁including ▁economic ▁ones . ▁ ▁Ex plan ation ▁for ▁the ▁L DP ' s ▁g rip ▁on ▁power ▁ ▁The ▁L DP ▁was ▁able ▁to ▁retain ▁power ▁for ▁ 3 8 ▁years ▁by ▁changing ▁both ▁its ▁political ▁st ance ▁and ▁political ▁leaders ▁according ▁to ▁changes ▁in ▁public ▁opinion ▁and ▁soci opol it ical ▁context . ▁ ▁For ▁instance , ▁when ▁Prime ▁Minister ▁Nob us u ke ▁K ishi ▁was ▁critic ized ▁by ▁the ▁public ▁for ▁his ▁high - hand ed ▁dealing ▁at ▁the ▁time ▁of ▁the ▁revision ▁of ▁the ▁Japan - Un ited ▁States ▁security ▁Tre aty ▁in ▁ 1 9 6 0 , ▁the ▁L DP ▁attempted ▁to ▁calm ▁public ▁diss atisf action ▁by ▁replacing ▁him ▁with ▁Prime ▁Minister ▁Hay ato ▁I k eda , ▁who ▁advoc ated ▁the ▁government al ▁s log an ▁of ▁“ tol er ance ▁and ▁p atience ” ▁and ▁concentr ated ▁on ▁the ▁dou bling - of - in come ▁policy . ▁When ▁people ▁experienced ▁serious ▁problems ▁ar ising ▁from