Attorney General Eric Holder Jr. entered office with all the confidence of someone who’s spent most of his career preparing for the job. But that swagger is about to be tested more than ever, as Republicans try to capitalize on months of attacks on the U.S. Department of Justice’s handling of terrorism cases.

Holder will head to the lawmakers’ territory for a hearing today before the Senate Judiciary Committee, his first since November. In the past four months, public opposition forced him to abandon plans to bring alleged Sept. 11 plotters to trial in lower Manhattan, while Republicans have hammered Holder for the government’s handling of the attempted Christmas Day airline bomber and for recent revelations he omitted some background materials during his confirmation process. Holder has also come under fire for hiring lawyers who in private practice had advocated for Guant�namo Bay, Cuba, detainees.