 For economic reasons, the success of the strategy of "la guerre de longue durée" would at very least require Britain to maintain a benevolent neutrality, preferably to enter the war as an ally as British sea power could protect French imports while depriving Germany of hers.A defensive strategy based on the Maginot Line was an excellent way of demonstrating to Britain that France was not an aggressive power and would only go to war in the event of German aggression, a situation that would make it more likely that Britain would enter the war on France's side.The line was built in several phases from 1930 by the "Service Technique du Génie" (STG) overseen by "Commission d'Organisation des Régions Fortifiées" (CORF).