Imperial wealth moving through an international commons makes the treasure fleets the maritime equivalent of exposed armoured-car convoys. Spanish silver and other colonial goods finance military power, so attacking those routes promises both private profit and strategic effect. Portugal responds to raiding faster than Spain by heavily arming merchantmen. Every gun and extra crewman displaces saleable cargo, while Portugal's smaller population and sailor base make it harder to increase the number of ships. Trade protection becomes a choice among firepower, carrying capacity, and fleet size.
Notable Point · 10:29-14:45
Treasure fleets make sea trade a strategic target
Spanish and Portuguese treasure trades illustrate why rich maritime routes attracted privateers and forced merchants to trade cargo capacity against armament.