In this usage, to "Copenhagen" an opponent meant taking it by surprise and seizing everything needed for resistance. The British also landed troops in 1807, unlike the predominantly naval attack of 1801. The second expedition joined sea power with troops ashore. That sudden, comprehensive seizure made Copenhagen a verb.
Notable Point · 7:26-7:50
What it meant to "Copenhagen" an enemy
In this shorthand, to "Copenhagen" an opponent meant taking it by surprise and seizing the means of resistance.