Ideology and policymaking | AP US Government and Politics | Khan Academy

Let's take a look at this chart based on survey data from the Pew Research Center. Researchers asked U.S. adults in early 2020 which issues they think should be top priorities for the President and Congress. The top two issues were the economy and the environment.

Now, as we compare that to other years, you can see that these two policy issues haven't always been top of mind. Although the economy has ranked first since 2002 until recently, jobs were second. The environment was in last place for several years, and climate change didn't even make the list until 2015.

So what's going on here? Questions like these help political scientists measure the policy mood of the public: people's preferences toward policy choices. As you can see, policy mood changes over time in response to problems and issues that arise. For example, in 2009, as a response to the economic crash, surveyed adults responded that jobs should be a top priority. But in 2020, after a period of economic recovery and low unemployment, jobs had fallen as a main concern, and new issues had taken their place.

Climate change has become a major concern for many people, which wasn't even a term that people knew a few decades ago. Conversely, a poll like this taken in 1980 might have shown containing communism as a main concern, but since the fall of the Soviet Union, that has dropped off the list.

These measures of policy mood help politicians and political parties craft their policy agendas in order to attract voters and serve their constituents. But if so many people think that the economy should be a major priority, why don't voters all just agree on a course of action?

Here's where ideological differences come into play. Political scientists sometimes divide policy issues into position issues and valence issues. Position issues are issues that divide voters, like abortion or gun control, where there isn't much room for overlapping opinions. Valence issues are issues that most voters will agree with, like our communities should be free of crime or we should care for the elderly.

These are high-level values that cut across partisan lines, but the parties might differ on how to achieve those outcomes. For example, although both Democrats and Republicans might want to reduce drug use, Republicans might argue that tougher drug laws are most likely to achieve that goal, while Democrats might argue that prevention and education programs would be more effective.

So, policy mood tells us what the public thinks is most important at any given time, but differing ideological beliefs about how best to achieve those priorities lead to different approaches on the left and the right.