Today saw major developments in Japan’s economy and politics.
From a sharp decline in the stock market to the government’s new economic and security policies, we provide a clear explanation of the most important topics you need to know right now.
- 1. Economy: Nikkei Average Plunges Over 1,000 Yen at One Point, Driven by U.S. Inflation Fears
- 2. Politics and Administration: Prime Minister Takaichi Orders Consideration of a Supplementary Budget
- 3. Science and IT: Inter-ministerial Meeting Held to Address Risks Associated with Advanced AI
- 4. Society: A Series of Incidents Involving “Mobile Battery Fires”—A Common Hazard
- Summary: Key Points to Watch
1. Economy: Nikkei Average Plunges Over 1,000 Yen at One Point, Driven by U.S. Inflation Fears
On the Tokyo stock market today, the 18th, the Nikkei Average plummeted, at one point recording a drop of over 1,000 yen compared to the previous trading day.
At one point, the index fell as low as the 60,300-yen range.
Main Causes of the Stock Market Plunge
- Risk of a Resurgence in U.S. Inflation
Following the release of U.S. economic indicators last week (such as the Consumer Price Index), market concerns have grown that interest rate cuts may be further off or that additional rate hikes could be on the horizon. - Sharp Rise in Long-Term Interest Rates
Japan’s long-term interest rates also temporarily reached the 2.800% range, marking their highest level in about 29 and a half years, which is weighing on the stock market. - A Wait-and-See Approach Following the U.S.-China Summit
In the wake of last week’s U.S.-China summit, investors are adopting a cautious stance, seeking to carefully assess the future implications for international trade and geopolitics.
2. Politics and Administration: Prime Minister Takaichi Orders Consideration of a Supplementary Budget
At a meeting of the Government-Ruling Party Liaison Council, Prime Minister Takaichi announced that she had ordered consideration of a supplementary budget, stating that the government would “make every possible preparation.”
The Purpose of Considering a Supplementary Budget
- Measures to Address Rising Prices and Soaring Energy Costs
As rising food and fuel prices are putting a strain on people’s livelihoods, we aim to provide prompt support for households and bolster the economy. - Disaster Preparedness and Infrastructure Strengthening
Drawing lessons from recent forest fires and earthquakes, it appears that securing budgetary resources to enhance disaster preparedness in regional areas is also being considered.
3. Science and IT: Inter-ministerial Meeting Held to Address Risks Associated with Advanced AI
An inter-ministerial meeting was held to discuss measures to address the risks associated with the widespread adoption of “advanced AI,” including ChatGPT.
Key Initiatives
- Development of Cybersecurity Defense Guidelines
We will expedite the creation of robust guidelines to prevent cyberattacks involving the misuse of AI and the spread of misinformation. - Promotion of Safe AI Utilization
We will develop infrastructure that leverages the benefits of AI while ensuring that confidential information belonging to the government and private companies is not leaked.
4. Society: A Series of Incidents Involving “Mobile Battery Fires”—A Common Hazard
This morning, a series of incidents occurred on trains in Tokyo (including the Tokyu Ikegami Line) in which mobile batteries brought aboard by passengers caught fire.
As a result, service on some lines was temporarily suspended, and some passengers sustained minor burns.
[Important] Tips for Using Portable Power Banks Safely
- Stop using any device that has been subjected to a strong impact or dropped.
- Choose reliable products that bear the PSE mark (certifying compliance with safety standards under the Electrical Appliance and Material Safety Act).
- If the device becomes abnormally hot while charging, stop using it immediately.
Summary: Key Points to Watch
Today’s news highlights how “global inflation and rising interest rates” are beginning to have a direct impact on Japan’s markets and household finances.
Attention will continue to focus on the details of the government’s supplementary budget and developments in legislation governing the rapidly advancing AI society.
(※This news summary is based on information as of May 18, 2026.)
