Japanese Prime Minister Fumio Kishida's controversial decision to begin discharging treated radioactive water from the Fukushima nuclear power plant into the sea on Thursday may deal another blow to his already unpopular government.

Kishida appears to hope that international events in September, such as a Group of 20 summit and the U.N. General Assembly, will allow him to prevent a further drop in his Cabinet's approval ratings by scoring some diplomatic achievements.

Japanese Prime Minister Fumio Kishida speaks to reporters at his office in Tokyo on Aug. 22, 2023. (Kyodo)

He is also considering reshuffling Cabinet members and executives of his Liberal Democratic Party in September, banking on the move garnering positive public attention and strengthening his influence within the ruling bloc.

In addition, Kishida apparently tried to avoid starting the water release after September in an attempt to mitigate the possible adverse effects on the LDP in local elections in prefectures near the Fukushima plant in the fall, sources close to him said.

Hiroshi Shiratori, a political science professor at Hosei University, said Kishida wanted to resolve one of the most complex issues at an early date with the aim of reversing the declining trend in support rates for his Cabinet.

But Kishida's envisioned scenario is unlikely to succeed, given that the contentious treated water discharge project has yet to be accepted by many voters, particularly local fishermen, due largely to insufficient explanation about the matter, pundits said.

Since the nuclear accident triggered by a devastating earthquake and tsunami in March 2011, the treated water has been kept in more than 1,000 tanks installed at the crippled facility, said the operator, Tokyo Electric Power Company Holdings Inc.

As the tanks are set to reach capacity in the not-so-distant future, Japanese political leaders were under pressure to make a swift judgment about when to release the treated water into the Pacific Ocean despite objections from residents.

Photo taken in June 2023 shows a crane barge anchored near where treated radioactive water will be released in waters off the crippled Fukushima Daiichi nuclear power plant. (Kyodo) 

In April 2021, Kishida's predecessor, Yoshihide Suga, approved a plan to discharge the water into the sea "in around two years," with the current government deciding in January to carry it out sometime "from spring to around summer" in 2023.

After the International Atomic Energy Agency gave the green light to Japan's project in early July, Kishida was forced to explore the most suitable timing to minimize the negative impact of the planned water release on his Cabinet and party, the pundits said.

Meanwhile, Kishida, who held the position of foreign minister for over four years, saw a resurgence in his popularity due to diplomatic actions. These included hosting a Group of Seven summit in his home constituency of Hiroshima, a city devastated by a U.S. atomic bomb attack in 1945.

In September, observers anticipate Kishida may again capture the spotlight during international conferences, potentially leaving a favorable impression on the public. Additionally, he is expected to undertake a Cabinet reshuffle to rejuvenate the image of his government.

Kishida's decision to begin discharging the treated water within August also came as key local elections will be held in the fall in Fukushima, Iwate and Miyagi -- prefectures hit hard by the nuclear crisis in 2011.

In early September, gubernatorial and prefectural assembly elections are slated to take place in Iwate Prefecture. In Miyagi and Fukushima prefectures, assembly polls are scheduled in October and November, respectively.

Some ruling lawmakers asked Kishida not to start releasing the treated water before the elections in Miyagi and Fukushima, claiming that the discharge would create headwinds for the LDP-endorsed candidates, the sources said.

Nevertheless, Kishida decided to proceed with the water release plan in August, believing that even if support for the LDP drops initially, he could regain approval ratings for his Cabinet through diplomatic events in September, they added.

Photo taken from a Kyodo News helicopter in February 2022 shows tanks used to store treated water on the premises of the crippled-Fukushima Daiichi nuclear power plant in northeastern Japan. (Kyodo)

However, pundits emphasized that Kishida faces an uphill battle in seeking public consensus on such an emotionally charged issue, noting that even his assurances on the safety of the treated Fukushima water might not allay prevailing concerns.

A Kyodo News survey showed in August that 81.9 percent of respondents said they perceived the explanation provided by the government on the issue as insufficient, while only 15.0 percent considered it adequate.

Hosei University's Shiratori emphasized that it is extremely difficult for Kishida to obtain understanding from those concerned about the water release, saying, "Safety proved by science and peace of mind felt by people are different stories."

A government source said the water discharge cannot be implemented as long as Kishida respects the opinions of all relevant parties, adding, "We have to settle the matter at an appropriate timing with our resolve to take full responsibility."

Even so, the government and TEPCO would be breaking their promise to local fishermen, worried about reputational damage to their seafood products, if they push ahead with the project without gaining consent from such individuals.

If news emerges that the government has proceeded with the water release despite local opposition, Kishida could face a nationwide voter backlash, potentially taking a "fatal toll" on his Cabinet, Shiratori said.

In recent months, approval ratings for Kishida's Cabinet have continued to slip against a backdrop of the Fukushima water discharge plan and a spate of registration errors and other administrative problems over the "My Number" national identification card system.

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