The sheer number of cleavages within any society has a lot to do with
whether it has amulti-party system, and thus is likely to be governed by
possibly unstable coalitions, or a two- or three-party system which may be
more likely to produce stable one-party governments. If any pattern exists in
the development of cleavages it is probably towards simplification, in particular
through a reduction in the importance of secondary cleavages. The Nether-
lands, for example, used to have a Roman Catholic party and not one, but two,
Protestant parties, which in 1980 merged to form a single Christian party. In
addition, other parties in the Netherlands have consolidated along conven-
tional class and issue lines, illustrating the declining importance of religious
cleavage.
Many cleavage patterns are essentially involuntary: a person is white, or has
been baptized and brought up Catholic or speaks a specific language by virtue
of birth, not as a matter of opinion or values. This is well demonstrated by the
example of Northern Ireland, split by a religious cleavage, where one cannot
escape the conflict by being an atheist—it will still be asked whether one is a
Catholic atheist or a Protestant atheist. Furthermore, research shows that there
is nothing in the specific theological differences between the two denomina-
tions which accounts for the hostility between the groups. The most enduring
cleavages are deeply historical in origin, closely bound with the development
of nationhood, and often outlive subsequent historical development. In the
USA, the North–South cleavage dates from before the Civil War (1861–65),
even though there are no longer any good economic reasons for people to see
their lives much affected by this particular distinction.
Coalition
Coalitions are groupings of rival political units in the face of a common enemy;
they occur in situations where protection from that enemy, or the furtherance
of some shared goal, overrides differences and potential conflicts between the
members of the coalition. Coalitions usually occur in modern parliaments
when no single political party can muster a majority of votes. Two or more
parties, who have enough elected members between them to form a majority,
may then be able to agree on a common programme that does not require too
many drastic compromises with their individual policies, and can proceed to
form a government.
Coalitions vary in their stability, their life expectancy, and in the way power
is distributed within them (which may or may not be related to the relative
sizes of the parties involved). Some coalitions are so long established, and so
obviously essential if the aspirations of either party are to be realized, that they
virtually comprise a new party in its own right. Thus the only hope of being in
government for the Liberal Democrats in the UK, the National Party in
Coalition