It’s from the well-known ‘70s radical-rightist pulp novel The Turner Diaries, as the day when the common white volk of America awaken, rise up, overthrow the captured-by-minorities-and-liberals government and hang race traitors and other enemies from streetlights.

It was the emotional payoff of the novel even though the sequence is pretty short and misaligned with the plot arc (because William Luther Pierce was a shit writer) and people forget how specifically fixated on white women who date black men it was, but it’s been an influential vision

So much so that rope-and-lampposts are (like helicopters) now a rightist-marked idiom for seizing control of society and executing your enemies, like guillotines for leftists, even though the French Revolution used lampposts too