"The Tree of Liberty must be refreshed with the blood of Tyrants and Patriots." means that if liberty is to exist, there will Forever be a struggle of Free people with the Forces of Tyranny.
About Paul Clayton Paul Clayton is the author of a three-book historical series on the Spanish Conquest of the Floridas-- Calling Crow, Flight of the Crow, and Calling Crow Nation (Putnam/Berkley), and a novel, Carl Melcher Goes to Vietnam (St. Martin's Press), based on his own experiences in that war.