I read a short paper, “Party System in a Divided Society: The Case of Belgium” written in 2000 by Vykintas Pugaciauskas (see below), who hypothesised why Belgium has remained a single-state entity, even with unrelenting centrifugal societal forces. His main thesis is that while political actors behave in an exclusivist way within the regions, at the higher federal level elites of the same parties co-operate in a typical consociational manner. The rank-and-file of the parties act freely in their locales but acquiesce in regards to agreements made across parties at the federal level.
The mode of cooperation, or Belgian consociationalism, is rather closed one where there is “natural” coalition of the Christian democrats and socialists expected. One important feature of these coalitions is their symmetry (as opposed to asymmetric strength — and asymmetric decline — of the two major parties in the linguistic regions) where the two regional parties of the same pillar join and leave the government together. These coalitions are then imposed on the regions thus pushing third parties out of cartel. Coalition pacts are carefully crafted by the central party elites and once they are reached the parliamentary parties are expected to follow them. The ministers still are considered as representatives of their respective regions and the party leadership is allowed to deviate from the coalition programs. The pattern of party organization and leadership selection further enhances the role of their central elites which are the most aware of the cooperation across the regional divide.Thus it might be concluded that the pillar parties engage in the dual behaviour. They pursue the regionalist agenda on the electoral level and in the regional councils but have to participate in the consociational arrangements on the central level. This makes them central actors with regard to federalism and increases the dependence of politics along the federal—regional dependence on the position of party elites. While until recently this has been a device safeguarding against the split up of the state, this was largely due to the fact that the vertical pillars that cut across the horizontal linguistic divide remained important despite the relative decline of the pillar parties. Yet further decline of the parties might put the federal system at risk.
I can foresee a consolidation of unionist and nationalist parties in Northern Ireland, with the foremost cleavage that of the constitutional issue. Yet I cannot see a replication of the Belgian model.First, “pillar parties” (i.e. unitary communal bloc parties) do not enjoy unanimous rule, let alone majoritarian control, of subregional administration (i.e. local government) in Northern Ireland, where majoritarian control contains significant minority representation of either communal bloc. Some district councils, notably that of Belfast City, have no overall control: the balance of power has been exercised by a non-aligned, centre party. Also, if there was a move towards consolidation of communal party representation (and one that was acknowledged/endorsed by the smaller of each communal party), then optimistically there would be an opportunity to also consolidate a redefined centre ground, which would include those not willing to join the consolidating parties. If not fractured, then such a centrist party would likely find itself exercise the balance of power in even more district councils, if not at the regional level. Pessimistically, the remnants of the communal blocs could leave political participation, and/or the centre ground vote (what Pugaciauskas calls “vertical pillars that cut across the horizontal [ethnic] divide”) could end up fatally fractured.