ary ▁and ▁dedicated ▁to ▁" the ▁Prime ▁Minister ", ▁Labour ▁leader ▁Harold ▁Wilson . ▁Cow ling ▁challeng ed ▁the ▁traditional ▁liberal ▁assumptions ▁over ▁the ▁reform ▁crisis ▁of ▁the ▁ 1 8 6 0 s ▁by ▁arg uing ▁that ▁the ▁Liberal ▁Party ▁was ▁not ▁the ▁straightforward ▁progress ive ▁party ▁that ▁wanted ▁to ▁hand ▁political ▁power ▁to ▁the ▁working - class ▁and ▁that ▁the ▁Conserv atives ▁did ▁not ▁promote ▁reform ▁in ▁reaction ▁to ▁working - class ▁pressure . ▁Cow ling ▁instead ▁placed ▁much ▁more ▁importance ▁on ▁parliament ary ▁man oe uv res . ▁Robert ▁Bla ke ▁thought ▁that ▁this ▁book ▁" g ives ▁the ▁most ▁convin cing ▁account ▁of ▁what ▁happened ". ▁ ▁In ▁ 1 9 7 1 ▁appeared ▁The ▁Imp act ▁of ▁Labour , ▁which ▁de alt ▁with ▁the ▁years ▁between ▁ 1 9 2 0 , ▁after ▁Labour ▁won ▁the ▁Sp en ▁Valley ▁by - e lection , ▁and ▁ 1 9 2 4 ▁when ▁the ▁Conserv atives ▁won ▁the ▁general ▁election ▁of ▁that ▁year ▁and ▁ended ▁the ▁Liberal ▁Party ▁as ▁a ▁real istic ▁party ▁of ▁government , ▁with ▁the ▁Labour ▁Party ▁emer ging ▁as ▁the ▁O pp osition . ▁ ▁In ▁ 1 9 7 5 ▁appeared ▁The ▁Imp act ▁of ▁Hitler , ▁dealing ▁with ▁ 1 9 3 3 ▁to ▁ 1 9 4 0 . ▁Cow ling ▁has ▁been ▁described ▁as ▁an ▁" is olation ist ▁imperial ist " ▁who ▁argued ▁that ▁from ▁Britain ' s ▁point ▁of ▁view ▁the ▁Second ▁World ▁War ▁was ▁a ▁" li ber al