Last week, as the cherry blossoms made their annual debut in Washington, D.C., the Capitol marked another anniversary: A year ago, Congress failed the nation by refusing to fix our broken gun background check system.In the year since, tens of thousands more Americans -- our mothers, our fathers, our friends -- have been killed with guns. Many of them would still be with us if a minority of senators hadn't blocked progress. By the way, this is not a tough political issue.