In troubled times, the memory of the Rev. Dr. Martin Luther King Jr. comes marching out of the nation’s collective past as both a reminder of our failings and a torchbearer for the ringing ideals to which our nation has long aspired — freedom, equality, justice.

And these are troubled times. Even with an economy that is doing well by many measures, at least for those already near the top, many Americans seem estranged from the nation’s legacy of idealism grounded in simple truths. Racial bigotry and anti-Semitism are resurgent in the darker corners of the national consciousness. Anti-immigrant sentiments powered by ethnic prejudices are driving significant aspects of national policy. Social media platforms are used as electronic gathering places for misfits whose sense of identity seems to be defined by whom they exclude, whom they hate.

Amid all this it is good to remember one of Dr. King’s more famous statements: “the arc of the moral universe is long, but it bends toward justice.”

And it is worthwhile to recognize and honor people who carry on the good fight, who seek to better the world. It doesn’t necessarily take a grand gesture to do this. Even small steps help us march toward that goal. Take the people who have signed up for the Community Emergency Response Team’s disaster preparedness class. They are giving their time to be prepared to help family, friends or neighbors in the event of a crisis. Or students at Wilton High School who collect socks for homeless veterans and active duty servicemembers. A sock may seem a small gesture but it can mean a lot to the person on the receiving end. Every day there are people who donate to Wilton’s food pantry, who make a “friendly visit” to a homebound person, who mentor students living in difficult circumstances.

Many of the troubling impulses that darken the discourse in America today can be seen as part of a backlash against the progress made by the movement that has its roots in the work done by King before his assassination in 1968.

Change is often generational. To those old enough to remember King as the living voice of the civil rights movement, the images of those tumultuous times — the marchers facing down police dogs and fire hoses, the little girls blown up in church — are a reminder that progress does come, though it may come with painful costs.

To younger folks, who know King as a civil rights leader they’ve read about, or seen in old news footage, the challenge now is to think — really think — about the shortcomings of the America King confronted half a century ago, the ideals of a better America that he fought for, and how both live on today.

King had a dream and gave his life for it — the dream of a truly equal, fair and just America. It falls to us to make sure that his dream lives and grows, and the arc of the moral universe continues bending toward an America that is better for all.