What can I say here? "You may have nothing to hide now, but this stays in the government records, and if you're liberal-leaning, the way things are going, you may find yourself in trouble in ten years?" Who's going to believe that the US will be hostile to liberals in ten years?

Who'd believe a month before the election that Trump would be president? Be cavalier with your personal data, but in my country we say "guard your clothes so you at least have half of them".