A study demonstrates that political divides have become deeper now, than at any other point in the last 50 years
A study led by the University of St Andrews analysing populist movements, such as the Brexit movement in the UK and the Trump campaign supported by ordinary citizens, found they disrupt established norms and act against democratic institutions.
The research found that over time, these established norms become associated with political identity, which leads to greater antagonism between opposing political parties.
The social inequalities underlying political movements
Social issues are central to political movements, such as racism in the United States, and they can be tackled by reducing social inequality. As well as this, they can be combatted through a united effort from all political movements to prevent these deepening divisions.
The research used mathematical and computational models to study how political attitudes and identities shifted over time in response to growing inequality, in an interdisciplinary collaboration between the Universities of St Andrews, Princeton and Pennsylvania.
The findings deduce the polarisation of people’s political positions to the rise of several populist political parties or movements who represent themselves as “against” the elite – this can be seen with Trump in the US, Modi in India, Le Pen in France, Bolsonaro in Brazil and the Brexit movement in the UK.
Dr Alexander Stewart of the School of Mathematics and Statistics at the University of St Andrews, who led the study, said: “We know that people have been becoming more politically polarised over time, for example in the US, but we don’t know exactly why political identity is becoming so important.
“We tried to understand this by developing a game theoretic model for the cultural evolution of party identity and comparing it to data.
“We found that if there is animosity or conflict between other types of identity group, such as different racial groups, people will tend to shift their political identities over time to match up with their racial identity, leading to political polarisation.
“This happens because it reduces conflict within a party. Factors such as inequality, which lead to greater animosity between identity groups, can trigger this process.”
Political parties have become more polarised in advanced economies
Dr Stewart added: “We found in the US for example that racial polarisation expressed by voters has declined while political polarisation between Republicans and Democrats has increased, and political parties have become increasingly sorted along racial lines.
“This suggests that antagonism between racial groups has shifted to become associated with political identities over time.”
When the researchers analysed whether reducing inequality through wealth redistribution could reduce polarisation, they concluded that it may assist actions that could reduce political polarisation, however it wouldn’t be enough to completely reverse polarisation on its own.
Dr Stewart said: “To reverse polarisation you must first remove the conditions that helped create it (for instance, reduce inequality) and then engage in ‘coordinated efforts’ to change attitudes such as signalling by political elites in the form of bipartisan cooperation or improved rhetoric about the ‘other side’.”