Chris Anders of the ACLU explains:
The power is so broad that even U.S. citizens could be swept up by the military and the military could be used far from any battlefield, even within the United States itself. The worldwide indefinite detention without charge or trial provision is in S. 1867, the National Defense Authorization Act bill, which will be on the Senate floor on Monday. The bill was drafted in secret by Sens. Carl Levin (D-Mich.) and John McCain (R-Ariz.) and passed in a closed-door committee meeting, without even a single hearing.While the Obama Administration may ultimately veto the legislation, the only way to ensure the bill doesn't pass is for the Senate to approve the Udall amendment, which would strip the detention provisions and require Congress to use an orderly process to consider whether any detention legislation is needed at all.
It is not too late to contact your senators and urge them to vote YES on the Udall Amendment to the National Defense Authorization Act.