Specifically, the proposal would prohibit the transfer of detainees to the United States and Yemen. The majority of the 127 detainees still being held — down from a high of about 680 — are from Yemen. But officials fear detainees who are released in Yemen, where al Qaeda commands a strong presence, could easily be lured into jihad.

“We know for a fact that … those who have been released have re-entered the fight and usually at a higher level because it’s a badge of honor to have been an inmate at Guantánamo Bay,” McCain said. He was flanked by Sens. Kelly Ayotte (R-N.H.), Richard Burr (R-N.C.), and Lindsey Graham (R-S.C.).

A senior State Department official noted on Wednesday that after Obama took office, the recidivism rate of released prisoners dropped significantly from 19 percent “confirmed of reengaging” to 6.8 percent.