Democracy as we know it is under attack around the world. In our own country, threats once hard to imagine have taken root: Voter suppression and foreign interference; misinformation and “fake news;” extreme polarization and gerrymandering. Starting today, the Ideas section is embarking on an ongoing look at the state of democracy — exploring the ways it has failed to live up to its promise, the forces that endanger it, and ways to shore it up for the future.