[Sidenote: Why Drake carried the war into the Pacific Ocean.]
It was Drake who first put into practice the policy of weakening Philip II. by attacking him in America. It served the direct purpose of destroying the sinews of war, and indirectly it neutralized for Europe some of Spain's naval strength by diverting it into American waters for self-defence. To do such work most effectively it seemed desirable to carry the warfare into the Pacific Ocean. The circumstances of its discovery had made Spanish America almost more of a Pacific than an Atlantic power. The discoverers happened to approach the great double continent where it is narrowest, and the hunt for precious metals soon drew them to the Cordilleras and their western slopes. The mountain region, with its untold treasures of gold and silver, from New Mexico to Bolivia, became theirs. In acquiring it they simply stepped into the place of the aboriginal conquering tribes, and carried on their work of conquest to completion. The new rulers conducted the government by their own Spanish methods, and the white race was superposed upon a more or less dense native population. There was no sort of likeness to colonies planted by England, but there were some points of resemblance to the position of the English in recent times as a ruling race in Hindustan. Such was the kind of empire which Spain had founded in America. Its position, chiefly upon the Pacific coast, rendered it secure against English conquest, though not against occasional damaging attacks. In South America, where it reached back in one or two remote points to the Atlantic coast, the chief purpose was to protect the approach to the silver mines of Bolivia by the open route of the river La Plata. It was this military need that was met by the growth of Buenos Ayres and the settlements in Paraguay, guarding the entrance and the lower reaches of the great silver river.