wedge issue

plural wedge issues

1. governmentA discussion point or a difference in points of view which is particularly likely to be controversial and a source of discord between discussants or other involved parties; a difference in viewpoints which causes disharmony within a political or social group.

   The speech . . . gave Democrats that rare gift: a wedge issue that split Republicans and united Democrats.

   2006 July 30, Nancy Gibbs, “Stem Cells: The Hope And The Hype”, in Time

   1 more example

   "It's sick," he gripes. "Everybody is tired of someone getting a job because of color." Republicans are exploiting such frustration. . . .. Says Kathy Spillar, national coordinator for the Feminist Majority: "The GOP wants to use it as a racial wedge issue."

   1996 March 25, Catherine Yang, “Worried white men may be the GOP's ace in the hole”, in businessweek.com, retrieved 11 May 2011