just two days later, both selem and walid were dead. the yemeni government said they had been killed by a u.s. drone strike. >> translator: we heard three or four massive explosions. rockets hitting from the sky. and we hurried up towards the mosque and found them. body parts all over the place. it was a dark and disastrous day. >> the yemeni government concluded the strike was what it called a u.s. mistake. one that provoked a furious backlash with an already-fragile u.s. ally. in time protests died down. but still grieving a year later, jaber said he took his search for answers to washington. >> translator: we were trying to directly find an explanation for what happened and why this car was hit when selem and walid were there. why now, what exactly took place in the moment, we need transparency, we needed answers. the war planes are still there overhead and no one knows who's likely to be the next victim. >> but jaber says he left washington with few answers about a program most americans don't even know much about. fast-forward now