Santos Costa was set to become one of the leading figures of the New State, the style adopted by the Salazar dictatorship, responsible for the reforms intended to improve the fighting efficiency of the Army. After the outbreak of the Second World War in 1939, he was also strongly associated with the faction in both the State and Army that desired a German victory, even though this went against the good relations that Portugal traditionally enjoyed with England. Although far more right-wing than Salazar himself, and something of a dangerous political maverick, he was finally appointed full Minister of War in 1944, because of his skill in ensuring that the Army remained an effective prop for the dictatorship.