SmartWater is a liquid with a unique identifier linked to a particular owner. “The idea is for me to paint this stuff on my valuables as proof of ownership,” I wrote when I first learned about the idea. “I think a better idea would be for me to paint it on your valuables, and then call the police.”
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If more people had a security mindset, services that compromise privacy wouldn’t have such a sizable market share — and Facebook would be totally different. Laptops wouldn’t be lost with millions of unencrypted Social Security numbers on them, and we’d all learn a lot fewer security lessons the hard way. The power grid would be more secure. Identity theft would go way down. Medical records would be more private. If people had the security mindset, they wouldn’t have tried to look at Britney Spears’ medical records, since they would have realized that they would be caught.

Bruce Schneier–Inside the Twisted Mind of the Security Professional (via)

This seems a little grim, but it would be a useful counterbalance to the general tendency to enthusiastly embrace any plausible-sounding proposal without thinking through the consequences.