With Los Angeles convulsed by confrontation between pro-migrant protesters and military units dispatched by Donald Trump, no figure apart from the president has loomed larger than Stephen Miller.

Behind the scenes, however, this has been the apogee of Miller’s power – and an episode that illuminated his power in a White House where his influence far outstrips his misleadingly modest title of deputy chief of staff.

Miller, 39, may have been the true catalyst for the volatile scenes that played out over several days in the city of his birth.