To give some sense of the scale of the disaster that would follow a failure, the US considered bombing that dam and releasing all that water in response to a potential chemical attack on US troops during Gulf War I, according to Colin Powell ( http://www.pbs.org/wgbh/pages/frontline/gulf/script_b.html - search for dams).
They considered an attack that would have killed ~1M people, presumably mainly civilians? sigh smh
There are people in the Pentagon considering all kinds of crazy scenarios all the time, so that when crazy actually happens the leaders can make a quick decision based on a briefing book that took a while to put together. It sounds ominous in the press, but it's really innocuous.