not about national security

a revealing bit at the end of this article:

Before being released from Guantánamo in February, Mr. Mohamed was offered a plea bargain, which required him to agree to abandon his efforts to obtain documents that might bolster his torture claims and not to file lawsuits against the United States government or any of its officials.

He rejected the offer and a few months later all charges against him were dropped.

it's not about national security, it's about covering their ass.