Reading a random news article to get the latest developments on this one:
http://www.ctvnews.ca/world/letter-fore ... -1.3002340
Uematsu began to tell people around him that disabled people needed to be killed. In February, he tried to hand deliver a letter he wrote to Parliament's lower house speaker demanding all disabled people be put to death through "a world that allows for mercy killing," Kyodo news agency and TBS TV reported.
Uematsu boasted in the letter that he had the ability to kill 470 disabled people in what he called was "a revolution," and outlined an attack on two facilities, after which he said he will turn himself in. He also asked he be judged innocent on grounds of insanity, be given 500 million yen ($5 million) in aid and plastic surgery so he could lead a normal life afterward.
The letter was reprinted by Kyodo after the attack.
"My reasoning is that I may be able to revitalize the world economy and I thought it may be possible to prevent World War III," the rambling letter says.
As sure as night follows day, we have a manifesto type forewarning by the attacker to the authorities which went unnoticed.
On an interesting side note, I think there could be subtext worth reading into here with regard to the attackers name Satoshi Uematsu. The name Satoshi is familiar because it's the same name of the alleged founder of digital currency bitcoin (Satoshi Nakamoto).
At first I thought the parts about demanding $5 million, revitalizing the economy, and preventing ww3, sounded like some kind of silly in-joke. Upon further thinking, and a quick google search, there may be more to it than meets the eye.
I found an article going back to May this year titled:
"Burned By Bitcoin Scandal, Japan Is Introducing Controls"
Japan’s new law is touted as an anti-money-laundering move.
Japanese lawmakers have passed legislation requiring virtual currency exchanges to be regulated by the Japanese financial services authority.
The country played host to one of the most prominent bitcoin exchanges, Mt. Gox, which collapsed in 2014 due to lax security and/or fraud—its users are still trying to claw back the millions they lost.
The episode led to a flurry of activity as no-one was quite sure who was responsible, or what the status of bitcoin actually was. At the time, the government said any regulation should be international in nature.
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The new law classifies virtual currencies as “asset-like values.” When it goes into effect a year after its finalization, it will require virtual currency exchanges operating in the country to register with the Financial Services Agency and verify the identities of their users.
The regulator said this was in order to “tackle issues of money-laundering and protect users.”
According to the Japan Times, exchange operators are keen on the new rules because they would improve consumers’ trust in the industry.
There are definitely some parallels to be drawn between these two stories. Japan are regulating bitcoin and "improving consumers' trust in the industry", which ties in with revitalizing the economy.