Issue selection, inequality, and polarization of social ideologies

In electoral competitions, political parties attempt to address key political issues, such as economic distribution problems and social issues (e.g., abortion and same-sex marriage). What factors prompt political parties to choose which issues to emphasize, and how does the strategy interact with their policy platforms? To answer this question, I develop an issue selection model between liberal and conservative parties with fixed social ideological positions and explore how issue selection strategies affect tax proposals. The findings reveal that the polarization of social ideologies motivates both parties to manipulate low-income/conservative voters' salience weights during the campaign stage. This pattern makes conservative parties emphasize the importance of social issues, while liberal parties emphasize economic distribution problems. Furthermore, in this equilibrium, if social issues are more newsworthy than economic issues, both parties advocate for tax reductions, contributing to an escalation in income inequality.