IT HAS LONG BEEN AXIOMATIC that as Spain rose or fell, in terms of wealth, morale, and power, so did her Empire. Nonetheless, some students of the Empire's history have recently questioned such a close correlation between the dynamics of mother country and colonies. The decline of Spain in the seventeenth century was not mirrored by developments in her colonies. Indeed, it has been postulated' that'there was no decline for the Empire as a whole in the seventeenth century, but simply a shift in the locus of its strength from Spain to her New World colonies.1 Furthermore, as the prosperity of the colonies rose in the seventeenth century and Spain gradually receded as a potent naval and maritime power, the colonials were forced to become increasingly self-reliant in the face of foreign threats. The colonies along the Pacific coast, isolated by geography from the vital Atlantic basin which supported Spain's primary connection with her American possessions, tended to be left to their own defensive devices, even more so than the Atlantic and Caribbean colonies. Metropolitan negligence and colonial growth contributed to the appearance of certain trends in regard to the defense of the