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Technology

Federalism and the Diffusion of Progressive Social Policies

Quick fact

In the United States, same-sex marriage was first legalized in Massachusetts in 2004 and gradually spread to over 30 states before the Supreme Court legalized it nationally in 2015—a classic example of state-level policy diffusion under federalism.

Why this is interesting

Why do some progressive policies spread like wildfire across states, while others stall for decades? The answer lies in how a nation shares power between its central and regional governments.