Presidents could order anyone arrested and imprisoned for life without charge or trial.
Abuse of power would replace rule of law protections.
Even someone erroneously arrested and cleared of wrongdoing could be held indefinitely without charge, given non-civil trials, none at all, or sent abroad to torture prison hellholes.
On November 29, the Senate voted 60 - 38 against Mark Udall's (D. CO) amendment. If adopted, it would have prohibited the military from arresting and imprisoning anyone anywhere without charge or trial, including US citizens.
An orderly review of presidential and congressional detention power would have been authorized. Before adjourning, House and Senate conferees will resolve the issue one way or other. Removing harmful provisions is doubtful.
If not, Obama promised a veto. So far, he's broken EVERY major promise made. Given enough congressional votes to override him, it hardly matters what he does.
December 8 is the House's targeted adjournment date. The Senate date is yet to be announced. Key legislation must be completed before leaving, including resolving language in FY 2012 NDAA.
Obama must then sign or veto it. Congress returns on January 5. Will he keep his promise or sign the bill to assure defense funding continuity? Electoral politics suggests the latter.