Apply to current events as you feel appropriate
Literally: black – white – divide / understand – bright
Alternately: A situation where it is easy to tell pros from cons, right from wrong, good fromd evil. As easy to distinguish and black and white.
Notes: This is a compound of compounds, of course. 黒白 is “black and white” (along with its concomitant metaphorical meanings); 分明 refers to “clear understanding.” Note that in some cases the first two characters may be switched to give 白黒 (in four-character compounds hakkoku, although in other contexts almost always shirokuro) without any change in meaning. On that note: while 白 is normally given the reading of haku in most compounds, in today’s yojijukugo only a voiced hyaku is considered correct.
Contrast 黒白混淆 (koku byaku kon kou), which refers to situations that are not a clear-cut “black and white,” but rather mixed together into shades of gray.
This phrase is attributed to our acquaintance the Luxuriant Dew of the Spring and Autumn Annals (Japanese 『春秋繁露』 = Shunjuu hanro).