Johnson’s aspirations to a military career were over. Now he faced removal from the Army. The well-liked, easygoing young black man whose friendships were described as colorblind was suddenly deeply shamed and ostracized.
People who knew him, both before and after, say he was never the same.
 Authorities have described Johnson as a loner who shot and killed five officers in downtown Dallas during last week’s peaceful protest over police shootings nationwide. President Barack Obama, at a memorial for the victims, called him “demented.”
Johnson wasn’t the best marksman, a fellow Army Reserve buddy recalled, and his former squad leader described him as less than motivated during training. But in Dallas, he showed striking tactical effectiveness, video from the scene shows. He moved stealthily, used columns for cover and swiveled his head to watch corners for threats.
Such was his skill that police initially thought they were taking fire from multiple snipers.