Five things everyone should know about political polarisation

The past few months have made it clear that divisions around the world are deepening. Research also shows that in Finland, public debate has become more fragmented than before. There is plenty of discussion about polarisation, but what does it actually mean?
Researchers Ali Salloum and Arttu MalkamÀki have published a handbook on polarisation in Finnish. It aims to help journalists, decision-makers, and citizens alike navigate an increasingly polarised environment. We explored five key aspects of polarisation that everyone should understand.
1. Small disputes grow into deep divides
A healthy and functioning democracy thrives on a diversity of values, attitudes, and opinions. However, in a polarised society, ordinary, everyday issues turn into battlegrounds because they become tied to deeper values and group identities.
Two striking examples from Finland illustrate this: the so-called âsparrow disputeâ and the controversy over a board game. The decline of sparrows in Finlandâs natural environment became a political fault line ahead of the 2024 UN nature summit. Meanwhile, decided to stop using the Afrikan tĂ€hti (âStar of Africaâ) board gameâseen as racist and colonialistâfueling cultural conflict.
Polarisation is more than just differing opinions; it leads to society splitting into opposing camps. This division manifests on three levels: in opinions, where views become more extreme and factions emerge; in interactions, where members of different groups stop engaging with each other; and in emotions, where hostility increases, understanding of the other side diminishes, and discussions focus more on discrediting the opposing group than on the actual issue at hand.
2. The intensity of polarisation variesâand so does its harmfulness
Some researchers focus on the factors that generate and accelerate polarisation, while others examine its consequences or measure its intensityâlike Ali Salloum and Arttu MalkamĂ€ki.
They use network science to measure polarisation, revealing, for example, how closely connected or how isolated different groupsâsuch as political party supporters or urban and rural populationsâare from one another. Their analysis draws on data such as voter questionnaire responses, political collaborations, and friendships that cross party lines.
Not all polarisation is harmful, but its intensity matters. Salloum and MalkamÀki describe polarisation on a scale ranging from low to extreme. At low levels, discussions remain constructive, and different perspectives can still engage with one another. As polarisation intensifies, distrust and hostility between groups grow, making societal decision-making more difficult. In extreme cases, opposing groups see each other as threats, and interaction between them nearly ceases.
This scale helps identify when societal tensions cross a critical threshold and begin to undermine democracy.
3. The spectacularisation of politics and social media algorithms fuel the spread of polarisation virus
Polarisation does not stem from a single cause but arises from the interplay of multiple factors. Economic inequality, globalisation, urbanisation, and increasing multiculturalism lay the groundwork for societal divisions, but they alone are not enough to create deep-seated antagonism. According to researchers, what truly matters is how these phenomena are framed and politicised.
Changes in the media landscape are one of the key drivers of polarisation. When politics becomes more like entertainment and the logic of media begins to dictate political decision-making, public discourse becomes more extreme. This effect is amplified in a politicised media environment, where news that aligns with a group's identity reinforces in-group loyalty and further entrenches opinions.
The way politicians communicate directly influences how citizens perceive one another. When political rhetoric becomes hostile and emphasises clear-cut oppositions, it becomes easier to dismiss the other side as an enemy. This, in turn, shapes everyday interactions and affects people's willingness to listen to differing viewpoints.
Environment also plays a role. If a person grows up and lives in an area where everyone shares the same views, their worldview is shaped accordingly. Segregated neighbourhoods can therefore reinforce political bubbles in which alternative perspectives are rarely encountered.
Today, discussions increasingly are shaped by social media platforms. Algorithms prioritise content that provokes strong emotions and divides audiences into echo chambers, further fuelling polarisation. Salloum and MalkamĂ€ki refer to this phenomenon as the polarisation virusâa rapidly spreading, provocative, and often decontextualised message that deepens societal divides.
Social media-driven fragmentation occurs in two key ways. Echo chambers emerge when a groupâs trust in external viewpoints erodes, leaving no room for opposing arguments. In information bubbles, alternative perspectives are not encountered at allânot because they are actively rejected, but because they never appear in the first place.
The polarisation virus can also spread into traditional media, overshadowing the structural issues that fuel conflicts. A striking example is the controversy that erupted in late 2024 when for having to attend a religious event, followed by the for religious themes. The debate quickly escalated into a symbolic battle of opposing sides, pushing the deeper, long-term issueâchildrenâs right to equal treatment regardless of beliefâinto the background.
Social media thus functions as the engine of the polarisation industry. It may not be the root cause, but it is a powerful accelerator. Platforms provide a space where like-minded individuals find each other, disagreements intensify, and misinformation spreads rapidly. If the shared foundation of reality begins to erode and facts become politically subjective, social media can shift from being a mere amplifier to becoming a direct driver of polarisation itself.
4. Polarisation is not a static state but constantly evolving
Political polarisation in Finland is not a straightforward phenomenon; its development depends on the perspective taken and the methods used to measure it. Studies in recent years indicate that opinion polarisation has intensified, particularly in debates on climate change and immigration. At the same time, divisions on certain issues, like immigration and NATO, have actually narrowed. While ideological divides have shown a slight increase, there is no clear evidence of widespread polarisation.
Digital environments appear to accelerate polarisation, but according to Salloum and MalkamÀki, their impact must be viewed with caution. Algorithms favour emotionally charged content, and people who are highly engaged in political discussions tend to be overrepresented in online debates.
Affective polarisationâa negative perception of opposing political groupsâhas grown stronger, particularly since 2019. Finland is not among the most polarised countries globally, but researchers warn that this does not mean it is immune to political tensions or their consequences.
, both in Finland and in many other parts of the world. Young and middle-aged women tend to support left-green parties, while men of the same age group lean towards the right. This divide not only influences voting behaviour but also affects broader societal attitudes and interactions between different groups. A striking example is the whose misogynistic rhetoric has resonated particularly with young men.
5. Polarisation fuels frustration, weakens decision-making, and harms mental health
Polarisation seeps into every aspect of life. Political divides influence cultural choices, residential patterns, and economic decisions, which can, in turn, restrict freedoms and lower the quality of decision-making.
While polarisation can initially boost political engagement, it often leads to fatigue and frustration over time. Many see political conflicts as increasingly negative, leading to alienation and eroding trust in the system. Rising hostility in public debate discourages political participation, a trend already evident in .
Polarisation can lead to flawed decisions and legislative gridlock, making it harder to tackle key societal challenges. This can result in misguided public investments and economic instability.
A concerning global trend is as perceived alternatives to democracy. Finland is not immune to this shift. Salloum and MalkamÀki stress the need to detect early signs of division and act before they escalate.
Polarisation does not only affect political and social structuresâit also has significant consequences for individual mental health. A deeply divided society is linked to rising levels of anxiety and depression.
Ultimately, polarisation is not just a concern for politicians, researchers, or journalistsâit affects everyoneâs daily life. According to experts, a polarised society needs citizens who understand the complexity of the issue and can navigate a divided environment constructively. But awareness alone isnât enoughâstrategies to reduce polarisation are crucial. Researchers suggest that political polarisation should be included in educational curricula at the upper secondary level. Raising awareness in workplaces, hobby groups, and communities could also help.
Ali Salloum and Arttu MalkamĂ€kiâs handbook on polarisation (in Finnish) was published as part of the DECAâDemocratic Epistemic Capacities in the Age of Algorithms project, funded by the Strategic Research Council SRC of Finland. It can be found .
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