Wedge issue

A wedge issue is a political or social issue, often of a controversial or divisive nature, which splits apart a demographic or population group. Wedge issues can be advertised or publicly aired in an attempt to weaken the unity of a population, with the goal of enticing polarized individuals to give support to an opponent or to withdraw their support entirely out of disillusionment. The use of wedge issues gives rise to wedge politics. Wedge issues are also known as hot button or third rail issues.

Political campaigns use wedge issues to exploit tension within a targeted population. A wedge issue may often be a point of internal dissent within an opposing party, which that party attempts to suppress or ignore discussing because it divides "the base." Typically, wedge issues have a cultural or populist theme, relating to matters such as crime, national security, sexuality (e.g. gay marriage), or race. A party may introduce a wedge issue to an opposing population, while aligning itself with the dissenting faction of the opposition. A wedge issue, when introduced, is intended to bring about such things as:

To prevent these consequences from occurring, the opposing party may attempt to take a "pragmatic" stand and officially endorse the views of its minority faction. However, this can lead to the defection of supporters of the opposing party's majority faction to a third party, should they lose the debate.

In Australia, "wedge politics" may sometimes be known as dog whistle politics, due to the practice of selective targeting so that only certain people will hear the message being pitched.

A case study of the use of wedge issues in practice comes from the 2001 federal election campaign in Australia. In early and mid-2001, a great deal of public attention was focused on boat people (asylum seekers arriving on unauthorised vessels), there having been several widely publicised landings of hundreds of people. On August 24, 2001, a ship illegally bearing 460 such people became distressed, and its passengers were picked up by the Norwegian cargo vessel MV Tampa.

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