Democrats are wrestling with how aggressively they will investigate the president and whether impeachment proceedings will ultimately be warranted. Publicly, the discussion has largely centered on worries about the political implications of moving forward. Some Democrats are concerned that aggressive oversight might trigger a backlash from voters; others worry that holding President Donald Trump accountable would only aggravate our already pronounced political polarization.

Democrats shouldn’t think this way. Accountability is essential to the long-term health of our democracy, more important than even healing the nation’s partisan divisions.

The United States learned this lesson 45 years ago. In August 1974, President Richard Nixon resigned from office in disgrace as soon as it became clear that the House would vote to impeach him for obstructing justice in the Watergate scandal and, moreover, that the Senate would likely vote to remove him from office. In a flash, Vice President Gerald Ford assumed the presidency.

Ford hoped to heal the nation from the trauma of Watergate, telling the country in his first official words as president that “our long national nightmare is over.”