As the chimes in the City Hall clock tower pealed “This Land Is Your Land” — Woody Guthrie’s anthem to American democracy — an impressive stream of Minneapolitans filled the hall’s rotunda Monday morning to witness the formal inauguration of a new mayor and a City Council on which seven of 13 members are newcomers.

The large assemblage was impressive not only because the outdoor temperature at inauguration time was minus 20. It was also notable for the extent to which its composition reflected the whole city. People who likely would have been scarce or absent at a similar gathering a half-century ago — women; immigrants; people of every color, religion and orientation — were out in force.

Rabbi Michael Adam Latz’s invocation recalled how his two grandmothers “lived on the edge of life in Minneapolis,” marginalized by anti-Semitism, sexism and, in one case, disability. Today, he said, “their great-granddaughters are home in Minneapolis. … They bore witness to a proud woman becoming their mayor, alongside a woman who is police chief and women heading the City Council, rising proudly with Somalis and Latinas and Hmong and Catholics and Protestants and Jews. … Everyone, home in Minneapolis.”

The arc of history has truly bent toward diversity and inclusivity in both Minneapolis and St. Paul. Whether history’s arc can also bend more nearly toward justice and opportunity for nonwhite, nonaffluent residents is an unanswered question. Making it so may be the greatest challenge these cities face if they are to remain prosperous in the 21st century.

Fortunately, it’s a challenge the mayors of both cities embrace. In St. Paul last Friday, Mayor Chris Coleman began his third term asking that his service be judged by its success in closing the educational achievement disparity between white and nonwhite schoolchildren. “I place this measuring rod before us today knowing full well that it will be the most difficult work we have ever done,” Coleman said.

First-term Minneapolis Mayor Betsy Hodges echoed that theme Monday with a stirring call to her city to “act like One Minneapolis” — not out of a sense of charity or obligation, but out of understanding that when “we become a true community … we restore ourselves fully as individuals.”

Neither mayor’s address was laden with policy prescriptions. Those came in the campaign, and they will come again in coming weeks in executive orders, City Council initiatives and bonding requests to the Legislature. Inaugurations are times to convey a vision and a summons to action by the citizenry as well as the government.

At that, both mayors succeeded. Coleman asked today’s St. Paulites to seek to emulate his grandparents’ generation. They were struggling immigrants, yet they raised the people now called the Greatest Generation. Today’s St. Paul residents need to be just as committed to bringing up today’s children, he said. Hodges described how strategically directing growth in Minneapolis can help close socioeconomic gaps in perennially lagging neighborhoods. She invited citizens to imagine Franklin Avenue as a Native American cultural corridor, East Lake Street as a cosmopolitan destination for food and culture, and West Broadway Avenue on the city’s North Side as a revived retail/residential corridor linked via streetcar to downtown and the region.

“If we do it right, we will begin to weave our city and our neighborhoods together fully, not merely in our conversations, but in our hearts and in our minds, as well. We will see One Minneapolis, and then we will know we can be One Minneapolis,” Hodges said. “What does this have to do with eliminating the disparities in outcomes we face? Everything.”

Hodges is right: Changing people’s thinking about the value of every part of the city is essential to closing the income gap, achievement gap, health gap and all the other income- and race-based disparities that afflict the Twin Cities. It will take vigorous use of the mayoral bully pulpit to spur that change. At that task, Coleman and Hodges have begun well.