RALEIGH, N.C. — On a Sunday morning more than two weeks after four U.S. soldiers were ambushed and killed in Niger, Rep. Walter Jones sat at the desk in his North Carolina office, doing what he’s done more than 11,000 times in 14 years: signing letters to families of the dead troops. “My heart aches as I write this letter for I realize you are suffering a great loss,” the letter begins. It’s a form letter, but the Republican congressman signs each one personally – penance, he says, for voting yes for the Iraq War in 2002. “For me, it’s a sacred responsibility that I have to communicate my condolences to a family,” Jones said.