A white person who publicly talks a lot of shit (fighting words, accusations, trash talks, belittles, etc) and then gets confronted in an extreme fashion for said shit talking.
The individual then proceeds to panic at the unexpected retaliation and cowards for protection in any and all forms possible. The individual may also literally shit their pants
Person 1: Yo homie, Donald Trump was talking shit on Mexicans until El Chapo said he'll kill him so The Donald called the FBI
Person 2: no way, what a milk shitter
Brought to public attention by Bob Woodward and Carl Bernstein in the book on the fall of Richard Nixon, All The President’s Men, ratfucker was Nixon’s term for a political operative who sows chaos among opponents; an agent provocateur. It is thought to have originated among campus political rivalries at USC, and seems to have some usage in the US military.
Along with Nixon’s other ratfuckers, Roger Stone caused fights at otherwise peaceful Democratic Party protests to generate a false narrative that the Democrats were violent and dangerous.