, ▁the ▁Union ▁may ▁act ▁only ▁if ▁an ▁action ▁cannot ▁be ▁sufficiently ▁achieved ▁at ▁the ▁Member ▁States ▁level , ▁and ▁could ▁be ▁better ▁achieved ▁at ▁the ▁Union ▁level . ▁ ▁Federal ist ▁v . ▁Inter g overn ment al ist ▁school ▁of ▁thoughts ▁ ▁Since ▁its ▁in ception , ▁the ▁European ▁Community , ▁then ▁becoming ▁the ▁European ▁Union , ▁has ▁faced ▁the ▁remarks ▁and ▁critics ▁of ▁two ▁main ▁school ▁of ▁thoughts : ▁the ▁federal ists , ▁def ending ▁a ▁central ised ▁decision - making ▁model , ▁and ▁the ▁inter g overn ment al ists , ▁in ▁favour ▁of ▁a ▁bro ader ▁share ▁of ▁compet ences . ▁▁ ▁On ▁one ▁side , ▁the ▁federal ist ▁school ▁is ▁in ▁favour ▁of ▁more ▁su pr an ational ▁dec isions . ▁For ▁them , ▁most ▁of ▁the ▁dec isions ▁should ▁be ▁taken ▁at ▁a ▁central ▁level , ▁by ▁the ▁Union , ▁in ▁order ▁to ▁improve ▁the ▁efficiency ▁of ▁decision - making , ▁enjoy ▁scale ▁econom ies ▁and ▁avoid ▁negative ▁sp illo vers ▁issued ▁from ▁local ▁dec isions . ▁The ▁fis cal ▁federal ism ▁theory ▁therefore ▁perce ives ▁the ▁principle ▁of ▁subs id iar ity ▁as ▁a ▁guarantee ▁that ▁the ▁dec isions ▁will ▁be ▁taken ▁at ▁central ▁level ▁when ▁there ▁would ▁demon stra ble ▁benefits ▁of ▁conduct ing ▁the ▁policy ▁by ▁the ▁Union . ▁▁ ▁On ▁the ▁other ▁side , ▁the ▁school ▁of ▁inter g overn ment al ism ▁def ends ▁a ▁decent ral ized ▁model ▁and ▁more ▁dec isions ▁taken ▁by ▁Member ▁States , ▁with ▁a ▁process