pertaining or devoted to one public issue only, especially a political one: single-issue voters.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for single-issue
Contemporary Examples of single-issue
There is such a thing in presidential primary politics as a single-issue deal-breaker.Be the Smarter Bush Brother, Jeb: Don’t Run!
December 17, 2014