If you have been assigned to the underclass any other identity you may covet and struggle to attain is a priori denied. The meaning of the 'underclass' identity is an absence of identity; the effacement or denial of individuality, of 'face'- that object of ethical duty and moral care. You are cast outside the social space in which identities are sought, chosen, constructed, evaluated, confirmed or refuted.
The 'underclass' is a collection of people who have had their 'bios' reduced to 'zoe'. The same fate meet the refugees - the stateless, the sans-papiers - the non-territorials in a world of territorially grounded sovereignty.
A most spectacular and perhaps even the most cosnequential, dimension of the planetary-wide expansion of the West has been the slow yet relentless globalization of the production of human waste, or more precisely 'wasted humans' - humans no longer necessary for the completion of the economic cyrcle and thus impossible to accomodate within a social framework resonant with the capitalist economy.

Bauman, Idenity.