▁Len in ▁port rayed ▁Imperial ism ▁as ▁the ▁closure ▁of ▁the ▁world ▁market ▁and ▁the ▁end ▁of ▁capital ist ▁free - comp et ition ▁that ▁arose ▁from ▁the ▁need ▁for ▁capital ist ▁econom ies ▁to ▁constantly ▁expand ▁invest ment , ▁material ▁resources ▁and ▁man power ▁in ▁such ▁a ▁way ▁that ▁necess itated ▁colonial ▁expansion . ▁Later ▁Marx ist ▁theoret icians ▁echo ▁this ▁conception ▁of ▁imperial ism ▁as ▁a ▁struct ural ▁feature ▁of ▁capital ism , ▁which ▁explained ▁the ▁World ▁War ▁as ▁the ▁battle ▁between ▁imperial ists ▁for ▁control ▁of ▁external ▁mark ets . ▁ ▁Len in ' s ▁treat ise ▁became ▁a ▁standard ▁text book ▁that ▁fl our ished ▁until ▁the ▁collapse ▁of ▁commun ism ▁in ▁ 1 9 8 9 – 9 1 . ▁ ▁As ▁the ▁application ▁of ▁the ▁term ▁" imper ial ism " ▁has ▁expanded , ▁its ▁meaning ▁has ▁shift ed ▁along ▁five ▁axes : ▁the ▁moral , ▁the ▁economic , ▁the ▁system ic , ▁the ▁cultural , ▁and ▁the ▁temporal . ▁Those ▁changes ▁reflect ▁a ▁growing ▁une ase , ▁even ▁s que am ish ness , ▁with ▁the ▁fact ▁of ▁power , ▁specifically , ▁Western ▁power . ▁ ▁The ▁relationships ▁among ▁capital ism , ▁imperial ism , ▁explo itation , ▁social ▁reform ▁and ▁economic ▁development ▁has ▁long ▁been ▁deb ated ▁among ▁histor ians ▁and ▁political ▁the or ists . ▁Much ▁of ▁the ▁debate ▁was ▁pione ered ▁by ▁such ▁the or ists ▁as ▁John ▁A . ▁Hob son ▁( 1 8 5 8 – 1 9 4 0 ),