Ezra Klein argues that the consequences of political polarization in the US system of governance are problematic. The constitutional system has enabled the Republican Party to retain political power with a homogeneous base that is shrinking as a percentage of the population. The numerical minority has been able to take control of the presidency and the Senate in the 21st century. In a context of changing demographics, Republicans have appealed to racial and religious identity to trigger fear and allegiance to themselves. The other party, the Democrats, are portrayed as the enemy. Bipartisan cooperation or compromise is increasingly viewed as a betrayal.

While the US is a republic with an 18th-century Constitution, the nation has been democratized via reforms throughout history. Its legitimacy comes from its status as a constitutional democracy, with fidelity to the rule of law, individual rights, and popular sovereignty. The repeated defeat of a numerical majority, especially a racially diverse one, by a numerical minority that is primarily white thus undermines the concept of popular sovereignty and the legitimacy of the government.

As the ancient Greek statesman Pericles argued, democracy requires a great deal more than majority rule.