It is the incomprehensible scale of the tragedy that silences you. There's the physical scale: A car perched on the roof of a three-story building in Minami Sanriku, or the 200-ton tug Kazumaru No. 1, swept 1,500 feet inland in the port of Ofunato, smashing every house in its path to splintered pulp.

The Kazumaru No. 1 tugboat, where the March 11 tsunami left it. Image courtesy WGBH.

But there's also the scale of the human tragedy. Rikuzentakata must once have been a stunningly beautiful coastal town. If you stand in the bay and look up at the mountains, the view is lovely, the mountains still and peaceful. But lower your eyes and the scene is of awful devastation. Where once there was a town of over 20,000, now there is a blasted mudflat.

I followed a group of perhaps 50 soldiers from the Japanese Self-Defense Forces, armed with bamboo canes, onto the mud. They formed a long line, waiting for the order, then set off on a careful yard-by-yard search.