Policy banning foreign powers from attacking one another in Japan

The policy banning foreign powers from attacking one another in Japan is Toranaga’s assertion that foreign conflicts do not carry their own authority onto Japanese soil. It blocks John Blackthorne from turning his European war against the Portuguese into a Japanese land operation, even when he argues that the attack would serve Toranaga’s interests. The rule makes permission to remain in Japan conditional on accepting Japanese jurisdiction, and places the decision about violence within the country in Japanese hands.

Authority and Scope

In Toranaga’s first interrogation of Blackthorne, the foreigner argues that his enemies are present in Japan and asks whether he may fight them there. Toranaga answers that foreigners are in the country by permission and that public mischief or quarrels are punishable by death. He insists that there is one law for all in Japan, refusing Blackthorne’s attempt to move from a question of trade and ship repairs to a claim of military freedom.

The policy is not presented as a general prohibition on warfare everywhere. Blackthorne describes his Dutch letters of marque as authorization from Holland’s legal rulers to carry war into places dominated by their enemies. Toranaga, however, examines that claim through a different political order, asking whether the Netherlands had rebelled against its former Spanish king. The exchange exposes the gap between Blackthorne’s account of lawful privateering and Toranaga’s concern with who has authority to fight within Japan. A commission recognized by one power cannot, by itself, settle what is permitted in another sovereign’s territory.

The Proposed Attack on Portuguese Interests

The conflict becomes explicit when Blackthorne outlines a plan to strike the Portuguese Black Ship. He says that, if Toranaga were at war with the Portuguese and wanted them harmed, two or three hundred disciplined fighters, a capable crew, and the Erasmus could board the ship and drag it out to sea. He frames the operation as a surprise attack whose timing Toranaga could choose. The proposal treats Japanese ports and forces as resources in a European contest; Toranaga rejects that premise.

Blackthorne also points to Portuguese control of Nagasaki and argues that, under his own law, he can attack an enemy anywhere. Toranaga answers that Japan is not merely another place in which European powers may pursue their quarrels. He will not permit one foreign nation to attack another on Japanese soil or foreigners to kill Japanese people. He draws a distinction for enemies of the Emperor, but that qualification does not authorize Blackthorne to launch the attack he has proposed. For Toranaga, the presence of Portuguese power in Nagasaki does not make Japanese territory available for a foreign private war.

The Boundary Between Land and Sea

Toranaga’s refusal does not erase the difference between action on Japanese territory and action beyond it. He says that Blackthorne may harry his Queen’s enemies on the high seas, while forbidding a land attack in Japan. The distinction leaves room for Blackthorne’s naval skills and English-Dutch hostility toward the Portuguese, but denies him the right to decide unilaterally where those hostilities may be carried out.

That boundary matters in a setting where maritime knowledge and control of ships shape political possibilities. Blackthorne’s proposal depends on the Erasmus, a trained crew, and a carefully timed boarding; his earlier account of a rutter likewise shows how closely safe passage depends on accumulated pilot knowledge. Yet command of a ship does not confer jurisdiction over the shore or its harbors. Toranaga’s policy makes the territorial limit decisive: foreign expertise may be useful, but its use remains subject to Japanese permission.

Enforcement and Political Stakes

Toranaga’s warning that public disorder will be answered with death gives the policy force beyond diplomatic disagreement. Foreigners are not treated as independent belligerents entitled to settle disputes among themselves inside the country. Their presence is conditional, and violence that breaches the host authority’s rules can be punished immediately. The policy thus links the treatment of Blackthorne’s military proposal to Toranaga’s broader insistence that all foreigners obey the same law while in Japan.

The rule also constrains Toranaga. Although Blackthorne believes the Portuguese are Toranaga’s enemies, Toranaga refuses to turn that shared suspicion into authorization for an attack. The Portuguese and Jesuits, meanwhile, tell Toranaga that Blackthorne is his enemy, deepening the mistrust around any foreign military undertaking. The policy is therefore both a prohibition and a claim of political control: neither Blackthorne’s commission nor another foreign power’s interests can decide who may wage war in Japan.