ACGB is the acronym for Acela Corridor Galaxy Brain, a phrase coined by
Christopher Balding, a renowned
economist and scholar in Sino-US-Europe study, to refer to a journo or tankie from Boston to the DC along the east coast who has
never left his town (e.g., Cambridge, the borough of Brooklyn, or Georgetown) but thinks he/she knows enough to run the world such. Acela is the "high speed" train line with a top speed of around 90 mph for brief stretches.