- Whether a state government is run by Democrats or Republicans didn't use to matter much in terms of policy-making, but there has been a massive divergence going on since the 1970s with a dramatic increase in divergence since 2000. https://www.cambridge.org/core/journals/perspectives-on-politics/article/from-backwaters-to-major-policymakers-policy-polarization-in-the-states-19702014/51dd7b022e358a99333447a6e2ba7b63 10 comments science