2.3.3.2 Radicalisation and polarisation tipping dynamics

Radicalisation can also exhibit tipping dynamics. Research has described radicalisation – for example, the spread of right-wing ideology (Youngblood, 2020) – through complex contagion processes. Similarly, the spreading of  extremist content on social media has been observed to follow contagion processes (Ferrara, 2017). Moreover, processes of ‘cross-pollination’ of radical ideas have been documented (Kimmel, 2018; Baele et al., 2023), including for climate denial (Agius et al., 2020). Cross-pollination describes the merging of previously separate radical clusters, facilitating further contagion by expanding the number of radicalised individuals and their reach to those not yet radicalised. 

Polarisation may increase quickly in response to fuelling of political partisanship and may be very difficult to reverse. Macy et al., (2021) found that polarisation is most likely when the issue that is meant to unite a society (e.g. facing the threat of climate change) is not as salient as the political partisanship. Radicalisation is also more likely in affluent societies, who are typically more sheltered from climate impacts but more likely to feel a threat to their status – and recent trends seem to confirm this (Vihma et al., 2021; Dunlap et al., 2016). 

In an extreme scenario, radicalisation tipping triggered by escalating Earth system destabilisation or breached Earth system tipping points, could lead to currently fringe political ideologies taking hold. One such example is ecofascism (Taylor, 2019), which reinterprets white supremacy ideology in the context of the climate crisis with the goal to defend habitable areas for the white race. Already, some recent right-wing terrorists have subscribed to and legitimised their actions with ecofascism, such as Brenton Tarrant, who committed a terror attack on a mosque in Christchurch, New Zealand, in 2019, killing 51 people. Finally, if radicalisation escalates we may also enter the pathway of a violent conflict (see Chapter 2.3.5).