However, if you still want to make a political statement, check out the Creative Commons 0 "public domain dedication" license.
It basically tries 20 different ways to waive all rights, falling back as many times as it needs to until it gets something legal in the licensee's jurisdiction.
I agree that the author's premise is flawed. Not licensing means "full copyright", which is the complete opposite of a protest. I don't believe anybody is releasing code with no license as a political statement. (Note: the author isn't endorsing this, just suggesting it's a reason for the lack of licensing on github. Near the end of the article, he suggests some better ways to make a statement.)
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