He wrote the "Coordinated offensive plan of land and sea against the United States of America" in 1804. In was submitted to Minister Dom Grandallana, returned apparently unread or uncommented upon. The plan submitted to the Spanish Admiralty for a full-scale war and invasion of the United States, involving naval and ground battles. Spain was becoming increasingly concerned at the growth of American power. The Third Coalition and the 1808 French destruction of the Spanish naval fleet saw this plan withdrawn.