But there are limits to the effectiveness of national ac
tion. Gaps are left which only the EU can fill. In order to reach its objectives, from the very outset the Treaty assigned a central role to fully-fledged common policies such as competition, trade, transport, agriculture and fisheries, and more recently EMU. There cannot be a true internal market and a customs union without precise rules to establish a level playing field. Without harmonising the great diversity of Member State
policies, internal border controls would ...[+++] have had to be maintained, the EU could not have spoken with one voice in international trade and sustainability
would have suffered in a downward spiral of negative competition.
Sans une harmonisation de la grande diversité des politiques des États membres, les contrôles aux frontières intérieures auraient dû être maintenus, l'UE n'aurait pas pu parler d'une seule voix dans les échanges internationaux et sa viabilité aurait souffert d'une spirale de concurrence négative.