Federal investigators were still struggling Monday to determine a possible motive for would-be Donald Trump assassin Thomas Matthews Crooks after a former high school classmate described him as “definitely conservative.” It “makes me wonder why he would carry out an assassination attempt on the conservative candidate,” Max Smith, who shared an American history class with Crooks two years ago, told the Philadelphia Inquirer. A bullet fired by the 20-year-old shooter, a registered Republican and member of a gun club, grazed Trump’s right ear that spattered his face with blood as he began a campa…