"A cascade of failures" is how the events leading up to the BP oil spill were described in the first day of Senate testimony by representatives of BP, Transocean and Halliburton - each of whom blamed each other for making the critical error that led to the disaster.
Folks, mark this down. Read the Senate testimony and digest its meaning. Because this is how engineering catastrophes - including ones with massive environmental consequences - happen. It's not just one thing that goes wrong - it's a series of small mistakes and errors of judgment that would be inconsequential on their own, but that taken together can be devastating.
Events like this are freakish and rare. But they are all but unavoidable, because the exact pathways by which they can occur are incapable of being mapped out in advance.
It's why it's generally a bad idea to play with fire - whether you're drilling for oil 5,000 feet under the sea, burying millions of metric tons of carbon dioxide underground, or generating power at nuclear plants. Engineers can try to anticipate and protect against every possible malfunction. They can create elaborate fail-safe mechanisms and safety systems. But accidents still happen. It's the way of the world.
And when they do, you had better have plans to deal with the consequences - an area in which BP has failed, and continues to fail, spectacularly.
So, as the oil industry CEOs look solemnly into the cameras and blame each other for causing the disaster, remember that the specific decisions made by BP, Transocean and Halliburton are only part of the source of blame for the spill. The original sin of the Gulf spill was drilling in deepwater in the first place, without an understanding of the costs or consequences.
It's a mistake we should avoid making again.