The duties of the principal secretary were not defined formally, but as he handled all royal correspondence and determined the agenda of council meetings, he could wield great influence in all matters of policy and in every field of government, both foreign and domestic. During his term of office, Walsingham supported the use of England's maritime power to open new trade routes and explore the New World, and was at the heart of international affairs. He was involved directly with English policy towards Spain, the Netherlands, Scotland, Ireland and France, and embarked on several diplomatic missions to neighbouring European states.