Kimimasa Mayama / EPA
Doves fly over Hiroshima Peace Memorial Park on Monday during a memorial ceremony to commemorate those killed by the world's first atomic bombing in 1945.
Updated at 12:42 p.m. ET: TOKYO - As dignitaries from 71 countries joined a crowd of 50,000 on Monday to mark the 67th anniversary of the Hiroshima atomic bomb attack, Japanese officials vowed to revamp energy policies in the wake of the devastating Fukushima nuclear accident.
"The government must learn from the lessons of Fukushima's nuclear accident and establish without delay an energy policy that guards the safety and the livelihood of the Japanese public," Hiroshima Mayor Kazumi Matsui told the crowd that had gathered in the scorching heat near the blast's epicenter to observe a minute of silence.
On Aug. 6, 1945, about 140,000 people were killed by an American atomic bomb that hastened the end of World War II. Another blast in Nagasaki three days later killed 70,000 more.
On August 6, 1945, the United States dropped the first atomic bomb used in warfare on the Japanese city of Hiroshima. Sixty-six years later, NBC's Brian Williams recalls the events leading up to the historic decision President Truman stood by for the rest of his life.
In March 2011, meltdowns at Tokyo Electric Power Co.'s Fukushima nuclear plant following an earthquake and tsunami caused radiation to spew over large areas of Fukushima, forcing more than 160,0000 people to flee. In the months following the world's worst nuclear crisis since Chernobyl in 1986, all of Japan's nuclear plants were shuttered.
While two reactors resumed operations in July, the Fukushima disaster has fueled widespread unease about the country's dependence on nuclear power.
Now, 17 months since the multiple explosions at Fukushima, efforts by the government of Prime Minister Yoshihiko Noda government to establish this new energy policy have finally started to gather momentum.
Aug 6, 2005: Sixty years ago, an atomic bomb was dropped on Hiroshima. It was one of the most consequential decisions any president has ever made. Harry S. Truman was faced with whether to use the newly developed bomb to end the war against Japan
Over the weekend, two days of deliberative polling -- which extracts informed and in-depth opinions through discussions and debate -- strove to determine the public's opinions on what the country's dependence on nuclear energy should be by 2030.
While in the past energy policies relied on opinions of industry experts, bureaucrats and politicians, a combination that a recent parliamentary investigation concluded had bred collusion and blindness when it came to ensuring nuclear reactors' safety, this time close to 300 citizens participated in the discussion.
Nearly a year after an earthquake and tsunami devastated Japan, Fukushima City residents fear the radiation is spreading outside of the government mandated exclusion zone. The government has asked residents to bury radiated soil in their own backyards, but how dangerous is the dirt and where should it go? NBC News Chief Foreign Correspondent Richard Engel reports.
Citizen participants judged three options, the first being zero dependence, which would be the most popular given the nuclear disasters the country has lived through. However, it would also mean higher energy bills and a stronger reliance on fossil fuel given that before the Fukushima disaster, 26 percent of Japan's energy was derived from nuclear power.
The second of option of 15 percent dependence would be attained if all of the current reactors were decommissioned after 40 years as is required by law now.
The third option -- 20 to 25 percent dependence on nuclear energy -- would require renewing current nuclear power plants.
But all of these options would desperately need new advances in the field of renewable energy, which currently provides a mere three percent of Japan's total energy, especially if the country continues to seek, clean affordable and safe energy.
Next, the government will sift through the opinions gathered at the citizen debates, make them public, and compile a draft of its new energy policy by the end of August.
Cleanup continues after last year's 9.0 earthquake and tsunami destroyed the Fukushima Daiichi nuclear plant in northern Japan.
Surrounded by testaments to atomic energy's devastating power in the Hiroshima Memorial Park, Prime Minister Noda promised that his government would follow through and make the difficult choices the country required.
"Under our fundamental policy to abandon the nation's dependence on nuclear power, we will strive to establish a mid-to-long-term energy structure, one (with) which the public will feel safe," he said.
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