It really doesn't matter if anyone else signs on to the treaty. The idea is that if the US signs on to the treaty, those in power can get allot of laws passed with no votes and no oversight. And, since treaties have the same weight as constitutional amendments, once we sign on to the treaty, those laws become very very difficult to get rid of.
I think the 'other countries' are more of a red herring and not really important to the ultimate goal of this treaty.
Who can say what that goal may be; certainly not our lawmakers, representatives, and press.
Secret courts, secret laws, secret treaties
My Administration is committed to creating an unprecedented level of openness in Government. We will work together to ensure the public trust and establish a system of transparency, public participation, and collaboration. Openness will strengthen our democracy and promote efficiency and effectiveness in Government.
-- Barack Obama