LANCASTER, Pa. — Last week I wrote about why political parties across the industrial world are fracturing from the top down. Today I’m writing about the political units that are working. On this Fourth of July, if you want to be an optimist about America, stand on your head. The country looks so much better from the bottom up.

I know — the current cliché is that we’re a country divided by two coasts, two coasts that are supposedly diversifying, pluralizing, modernizing and globalizing, while in flyover America everyone is high on opioids, cheering for President Trump and waiting for 1950 to return. That’s totally wrong.

Our country is actually a checkerboard of cities and communities — some that are forming what I call “complex adaptive coalitions” and are thriving from the bottom up, and others that can’t build such adaptive coalitions and are rapidly deteriorating. You can find both on the coasts and both in the interior — and you can find both in just one little corner of south-central Pennsylvania.

I was invited in April to give a paid book talk here in Lancaster, and I was so blown away by the societal innovation the town’s leaders had employed to rebuild their once-struggling city and county that I decided to return with my reporter’s notebook and interview them.

My original host was the Hourglass, a foundation founded by community leaders in Lancaster County in 1997, when the city of Lancaster was a crime-ridden ghost town at night where people were afraid to venture and when the county’s dominant industrial employer, Armstrong World Industries, was withering.

Some of the leading citizens decided that “time was running out” — hence “Hourglass” — and that no cavalry was coming to save them — not from the state’s capital or the nation’s capital. They realized that the only way they could replace Armstrong and re-energize the downtown was not with another dominant company, but by throwing partisan politics out the window and forming a complex adaptive coalition in which business leaders, educators, philanthropists, social innovators and the local government would work together to unleash entrepreneurship and forge whatever compromises were necessary to fix the city.

Pretty much the exact opposite of what’s happening in Washington, D.C., today.

For my 2016, “Thank You for Being Late,” I profiled the complex adaptive coalition — called the Itasca Project — that had emerged to re-energize my hometown, Minneapolis. I’ve since seen such coalitions popping up all over the world — from Knoxville, Tenn., to Sheridan, Wyo.; from Broward County, Fla., to Birmingham, Ala.; and from Mexicali, Mexico, to the Western Galilee in Israel.

One of the most successful is Hourglass, which defined its mission as being a “trusted source for information, innovative ideas and insights that will help stakeholders, elected officials and voters make more informed and enlightened decisions” to advance the community. In these dark days of our national politics, these emerging coalitions are a real source of optimism for me.

At 7:30 Friday morning in early June, the Hourglass leaders in Lancaster were all sitting around the kitchen table at Art Mann Sr.’s house, as they do every Friday. The seven men and women representing different Lancaster societal and business interests were discussing the region’s shortage of clean water, because of farm runoff, fertilizer and salt on the street.

None is in city government or an elected politician; they’re just respected volunteer community activists who will make a recommendation, based on research, to the city or county to get a problem fixed and help galvanize resources to do it. They all know one another’s party affiliation, but they’ve checked them at Mann’s front door.

“The key to it all is trust,” Mann explained to me. “Politically we are all different, and our experiences are different. You can only get progress where there is trust. People trust that we are not in it for personal agendas and not partisan agendas. We will often host elected officials, and they will throw out ideas and we will give them feedback. And they are not worried it will go out of this room.”

As the breakfast wore on, I was reminded of the business philosopher Dov Seidman’s dictum that “trust is the only legal performance-enhancing drug.” And I recalled Israeli societal innovator Gidi Grinstein’s dictum that what is saving so many communities today is “leadership without authority — so many people stepping up to lead beyond their formal authority.”

Mann, a Republican local metals manufacturer who began his civic life running for the school board, was one of the original conveners of Hourglass — after looking around Lancaster in the early 1990s and seeing a county that was hemorrhaging jobs and a city that was dying and wholly unprepared for the 21st century.

“My family has been here since 1740 and was always interested in public service,” Mann told me. “We could see that in the late ’90s that the county was going to hell if we didn’t do something. People thought the city was unsafe. If we let the city die, it would affect the whole county.”

Greater Lancaster is a microcosm of America. The city has a population of 60,000, about 40 percent of whom are white, 40 percent Latino — mostly Puerto Ricans whose parents came decades ago to process chickens. About 15 percent are African-Americans, and the rest are a rainbow of Asians and immigrants and refugees from as far afield as Afghanistan, Nepal, Iraq and Syria. The city, though, is ringed by largely white suburbs — and beyond them a countryside dominated by Amish and Mennonite farmers and crafts people. The county’s total population is about 600,000.