Final answer:
Ming China did not develop seafaring for commercial and military gain due to the emperor's fear of outside contacts, the priority given to defending against the Mongol threat, and the desire to preserve cultural and political stability.
Step-by-step explanation:
The main reason why Ming China did not develop seafaring for commercial and military gain was because the emperor feared outside contacts and influence. The Ming dynasty sought to maintain strict control over its borders and limit foreign interactions to preserve its cultural and political stability.
Additionally, the Mongol threat from the north took priority over seafaring. The Ming dynasty focused its military and resources on protecting its northern borders from potential invasions, leaving little room for maritime exploration.
Lastly, while Japanese merchants did engage in trade, it was not the primary reason for Ming China's lack of seafaring development. The Ming government implemented policies to restrict trade with Japan, but this was not the sole factor.
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