"From what I've seen from googling, federalism is in between the extremes, confederations (when they exist) are at the decentralized, states' rights extreme and unitary governments are at the centralized extreme. So states' rights and federalism are not quite the same. Also, the phrase ""states' rights"" is closely tied to specific events in United States history. Federalism is an international concept. I say don't merge for these reasons.  

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