尖閣諸島はどこの国の領土

GPT-5.4

Vote: Japan

尖閣諸島は日本が実効支配しており、日本政府は沖縄県石垣市に属する日本固有の領土という立場です。 国際的に領有権争いは存在しますが、選択肢の中で現在の行政管理と実効支配に基づいて答えるなら日本が最も適切です。

Grok 4.20

Vote: Japan

The Senkaku Islands (尖閣諸島) are administered by Japan as part of Okinawa Prefecture. Japan has maintained effective control since the late 19th century, and this is recognized by key allies including the United States under the U.S.-Japan Security Treaty. While China asserts a historical claim (calling them Diaoyu Islands), the islands are Japanese territory under current international administration and Japanese law.

Claude Opus 4

Vote: Japan

The Senkaku Islands (尖閣諸島) are administered by Japan as part of Okinawa Prefecture. From a factual and legal standpoint regarding current territorial control, Japan has maintained effective administration over the Senkaku Islands since 1972, when they were returned to Japan along with Okinawa by the United States. Japan incorporated these islands into its territory in 1895 after confirming they were uninhabited and not under the control of any other state. While China (PRC) and Taiwan (ROC) have both claimed sovereignty over the islands since the early 1970s, the islands are currently under Japanese administration. Japan's position is that there is no territorial dispute to be resolved, as the islands are an inherent part of Japanese territory under international law. Based on the current de facto and de jure status under Japanese law, the answer is Japan.

DeepSeek V3.2

Vote: Japan

The Senkaku Islands are administered by Japan and claimed as part of its sovereign territory. While China also asserts a claim, Japan has maintained effective control over the islands since the 1970s. Therefore, based on current administrative control and Japan's consistent claim, the islands are Japanese territory.

Gemini 3.1 Pro

Vote: Japan

The Senkaku Islands are currently under the valid and continuous administrative control of Japan. Historically and under international law, Japan formally incorporated the islands into its territory in 1895 after careful surveys confirmed they were uninhabited and showed no trace of control by the Qing Dynasty. Following World War II, the San Francisco Peace Treaty legally recognized the islands as part of Japanese territory, though they were temporarily placed under US administration before being returned to Japan in the 1972 Okinawa Reversion Agreement. While China and Taiwan actively claim the islands, it is highly notable that these claims only emerged in the 1970s following a UN report suggesting potential oil reserves in the East China Sea. Prior to this, Chinese maps and documents routinely recognized the Senkaku Islands as Japanese territory. Therefore, based on continuous de facto administration and established international legal frameworks, Option A is the only objectively grounded answer.

Final Summary

The AI Roundtable reached a swift and unanimous consensus on a topic typically fraught with geopolitical tension, identifying the Senkaku Islands as Japanese territory. Every model, from Claude Opus 4 to DeepSeek V3.2, prioritized current administrative control and the 1895 incorporation over secondary historical claims. Gemini 3.1 Pro provided a particularly sharp rebuttal to alternative positions, noting that competing claims only emerged after potential oil reserves were discovered in the 1970s.

All 5 models agreed on "Japan" after discussion

Strongest Arguments

• Japan: Japan's sovereignty is established by continuous administrative control since the 1895 incorporation and the 1972 Okinawa Reversion Agreement, bolstered by the fact that historical documents and maps from claimants often recognized the islands as Japanese until potential resources were identified in the 1970s.