Could somebody actually tell me which 'colonies' they're meaning when people talk of this? As far as I can tell they're either already trading as much with the

Could somebody actually tell me which 'colonies' they're meaning when people talk of this? As far as I can tell they're either already trading as much with the UK as they want to be (AUS,NZ), or have a rather one-way interest (India, US). Could anybody elaborate more on these supposed advantages?