A familiar sight along Tohoku's Sanriku coastline are the tsunami stones erected by past generations that alert residents to the high-water mark of previous tsunami and the perils of building any closer to the sea.

Over time these warnings were ignored, and those who lived in dangerous coastal lowlands behind protective seawalls developed a false sense of security. Many of these massive barriers were smashed apart on March 11, 2011, as the sea engulfed and pulverized everything in its path. But even if the seawalls nurtured a dangerous complacency, town officials understood that other countermeasures were essential to reduce risk.

On the anniversary of the Sanriku quake and tsunami of March 3, 1933, many schools along the Tohoku coast conduct annual evacuation drills. That meant teachers and students were prepared just over a week later in 2011 when faced with the real thing. The annual disaster emergency exercise saved many lives among coastal dwellers who knew better than to ignore risk or wish it away. Of course even the best drills and evacuation plans can't fully confer safety, because sometimes preparations can be inadequate, and catastrophic events amplify the risk of human error.