I believe it's"Japan allowed less European trade after the Spanish conquered the Philippines, so traders hired private armies to force access to Japan".
The answer is: Japan allowed less European trade after the Spanish conquered the Philippines, so traders hired private armies to force access to Japan
At that time, the traders need permission from japan in order to gained the trade access. (since other trading paths are filled with pirates that can steal their products). The traders hired private armies in order to create safe paths for their travel and to intimidate Japanese local government when they arrive to japan and sell their products.
It resulted in a stalemate which meant that the USA had a distant threat but still a threat it also resulted in a trading partner and a loyal Allie in the pacific area
