Why does Obama want Trans-Pacific Partnership to pass so badly?

In promoting a proposed trade pact covering 12 Pacific Rim nations, President Obama has cast the initiative as an instrument of equity. The Trans-Pacific Partnership (TPP) would, in his words, “level the playing field” and “give our workers a fair shot.” But critics argue that within the hundreds of pages of esoteric provisions, the deal -- like similar ones before it -- includes a glaring double standard: It provides legal rights to corporations and investors that it does not extend to unions, public interest groups and individuals.

http://www.ibtimes.com/trade-pact-how-trans-pacific-partnership-gives-corporations-special-legal-rights-1975817