 The brothers were divided in their policies.Thomas retained hope that the Papacy might yet call for a crusade to restore the Byzantine Empire whereas Demetrios, probably the more realistic of the two, had more or less given up hope of Christian aid from the West and believed it to be best to placate the Turks.Hopes for a crusade were not completely ridiculous; though no crusade ever materialized, preparations had been made in the 1450s following Pope Nicholas V's 1453 crusading bull "Etsi ecclesia Christi".