The original story that the WSJ based theirs on

http://complex.foreignpolicy.com/posts/2013/12/24/power-station-military-assault

I don't think this was a coventional terrorist attack. Eco-terrorist maybe, but blasting away at a single substation that didn't cause a power outage seems fairly ineffective in light of the vulnerabilities exposed by the September 2011 power outage in SoCal.

IMHO, it's too premeditated to be just vandlism. I think it's just one disgruntled individual and not a terrorist dry run.
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The object in life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane