Definition
To divert negative political attention by use of a military operation.
Origins
From the tail wagging the dog / the tail wags the dog, first used in the 1858 play, Our American Cousin. The shortened form with the political sense was popularized by the film Wag the Dog (1997).
How People Actually Use It
to cause a persuasive movement in any large body of influence, i.e., a mass of people, through means by which a lesser influence is utilized. From the phrase, 'It's the tail that wags the dog.' This can be seen when a dog begins to wag it's tail, and it's body then follows.
"in partisan politics, an unpopular party will wag the dog using a variety of provocative political manoeverings and machinations to undermine the public favour from the popular party, out of which a momentum can be borne."
Source: Urban Dictionary