No, plagiarism and copyright infringement are not the same thing

Within a post at Forbes titled A Tale of Plagiarism: So Avoidable, So Detectable, one finds plagiarism and copyright infringement improperly interrelated:

It’s not unusual for writers, when they’re unable to get a comment or information on their own, to lift a quote or a paragraph from a newspaper, magazine article or book. But when that is done, credit must be given by attributing the quote or information to the original source. It’s legal – and ethical – to do that, according to the fair-use law, but only if it’s not overdone and not too much text is used. Short of that, it’s flat-out plagiarism – passing off someone else’s words as your own, which violates U.S. copyright laws. It’s the same as stealing.

Passing off Shakespeare as your own is plagiarism, but does not violate any copyright laws. The author of the piece needs to review the Dastar decision.