Political Cortex: Brain Food for the Body Politic

'1982 -- Soviet gas pipeline. Operatives working for the Central Intelligence Agency allegedly (.pdf) plant a bug in a Canadian computer system purchased to control the trans-Siberian gas pipeline. The Soviets had obtained the system as part of a wide-ranging effort to covertly purchase or steal sensitive U.S. technology. The CIA reportedly found out about the program and decided to make it backfire with equipment that would pass Soviet inspection and then fail once in operation. The resulting event is reportedly the largest non-nuclear explosion in the planet's history.'

Wired does fudge a bit. From the article they link to:

"The result was the most monumental non-nuclear explosion and fire ever seen from space," he recalls, adding that U.S. satellites picked up the explosion.

Wikipedia says the  Halifax Explosion in 1917 was the worst man-made, non-nuclear explosion.  (Of course, they didn't have satallites in 1917.) Yet whichever explosion was actually bigger in terms of kilo/mega? tonnage, the bug which caused the Soviet gas explosion still had a most profound effect on World History.

"While there were no physical casualties from the pipeline explosion, there was significant damage to the Soviet economy," he writes. "Its ultimate bankruptcy, not a bloody battle or nuclear exchange, is what brought the Cold War to an end. In time the Soviets came to understand that they had been stealing bogus technology, but now what were they to do? By implication, every cell of the Soviet leviathan might be infected. They had no way of knowing which equipment was sound, which was bogus. All was suspect, which was the intended endgame for the entire operation."

That's big.

The article also tells us that the first bug ever found was actually a REAL bug:

' [I]n 1945 engineers found a moth in Panel F, Relay #70 of the Harvard Mark II system. The computer was running a test of its multiplier and adder when the engineers noticed something was wrong. The moth was trapped, removed and taped into the computer's logbook with the words: "first actual case of a bug being found."'

 The moth may have been the first found computer bug, but given that the tiniest piece of code can produce such immensely disasterous consequences, the butterfly really seems a more appropriate poster child.