At 2:46 Monday afternoon, Japan went quiet.
In memory of the lives lost two years ago in the earthquake that struck at that hour and the tsunamis that followed, a moment of silence was held across the country. From government buildings to small coffee shops, everyone paused -- the Emperor of Japan, politicians, national TV anchors, office workers. In Tokyo the busy subways were shut down briefly, and in some areas drivers pulled over to the side of the road.
At the same time on Twitter, an argument broke out.
At exactly 2:46 many users posted "Mokutou," Japanese for "silent prayers," followed immediately by angry responses along the lines of "You're not praying silently if you tweet about it," and a lengthy online back-and-forth ensued.
The 2011 earthquake and tsunami are forever linked with social media in Japan. In the chaotic days and weeks that followed, with the northeast coast in shambles and hundreds of thousands in shelters with no phone service, many turned to services like Twitter and Facebook to post personal news or keep in touch.
The surge in use drove such sites into the mainstream, where they have remained since. Japanese users that had long been unwilling to use their real names online, sticking to local anonymous networks like Mixi, were suddenly revealing the names of dead relatives and posting pictures of their ruined homes.
"People had lost their homes and families, but they wanted to keep track of what was happening," said Hatsue Toba, a 51-year-old who survived the tsunami in the coastal town of Rikuzentakata, much of which was flattened by a tsunami.
Many residents left the area, but Toba stayed in town and started a small vegetable shop to help local farmers recover.
"At first people didn't have computers, but they could use the Internet with their phones," she said.
Toba made a Twitter account in June and one on Facebook in December, and is still active on both today. Her daily "Good morning" posts are famous among former residents scattered across the country, and her vegetable store became a meeting place when they returned to visit.
Minako Miyamoto, a nurse who lives in the unaffected city of Kanazawa on the western coast of Japan, rushed east to volunteer when she learned how serious the local situation was, and eventually launched a nonprofit to help.
"Before the disaster, I used Mixi, Facebook, and Twitter. But on Mixi, many people are anonymous, while on Facebook people use their real names, so it is more trustworthy," she said. "Even now, I use Facebook to keep in touch with people I met in the shelters."
Statistics show that users of both services have surged since March 2011. In February of that year, Twitter was averaging about 130 million messages a day in Japan, a number that has since climbed to 400 million. The company declined to provide exact user numbers for the country, but Japanese users are among its most numerous and active.
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