The Fourth of July is the birthday of American exceptionalism — originally, the idea cherished by the nation's Revolutionary founders that the practice of liberty, equality and democracy in these United States would kindle hope in a world downtrodden by every form of despotism, hierarchy and oppression.

Independence Day marked the determination of a new and diverse people to throw off the old yoke of hereditary rule, with all its attendant traditions of social and economic stratification. The founders believed that America would inspire other nations as an ally and friend, rather than dominate them by force of arms or money. They did not regard their weak new republic as intrinsically superior or chosen to rule the world by God — but argued instead that the ideals of popular sovereignty and constitutional freedom represented the natural rights and the future of humanity everywhere.

So July 4 is a holiday whose meaning still resonates, despite centuries of contradictory history and circumstance. And it ought to be a day ...

Evidence supporting the existence of climate change is pummeling the United States this summer, from the mountain wildfires of Colorado to the recent “derecho” storm that left at least 23 dead and 1.4 million people without power from Illinois to Virginia. The phrase “extreme weather” flashes across television screens from coast to coast, but its connection to climate change is consistently ignored, if not outright mocked. If our news media, including—or especially—the meteorologists, continue to ignore the essential link between extreme weather and climate change, then we as a nation, the greatest per capita polluters on the planet, may not act in time to avert even greater catastrophe.

More than 2,000 heat records were broken last week around the U.S. The National Oceanic and Atmospheric Administration (NOAA), the government agency that tracks the data, reported that the spring of 2012 “marked the largest temperature departure from average of any season on record for the contiguous United States.” These record temperatures in May, NOAA says, “have been so dramatically different that they establish a new ‘neighborhood’ apart from the historical year-to-date temperatures.”

In Colorado, at least seven major wildfires are burning at the time of this writing. The Waldo Canyon fire in Colorado Springs destroyed 347 homes and killed at least two people. The High Park fire farther north burned 259 homes and killed one. While officially “contained” now, that fire won’t go out, according to Colorado’s Office of Emergency ...

Fenway Park, Boston, July 4, 2011. On this warm summer day, the Red Sox will play the Toronto Blue Jays. First come pre-game festivities, especially tailored for the occasion. The ensuing spectacle -- a carefully scripted encounter between the armed forces and society -- expresses the distilled essence of present-day American patriotism. A masterpiece of contrived spontaneity, the event leaves spectators feeling good about their baseball team, about their military, and not least of all about themselves -- precisely as it was meant to do.

In this theatrical production, the Red Sox provide the stage, and the Pentagon the props.  In military parlance, it is a joint operation.  In front of a gigantic American flag draped over the left-field wall, an Air Force contingent, clad in blue, stands at attention.  To carry a smaller version of the Stars and Stripes onto the playing field, the Navy provides a color guard in crisp summer whites.  The United States Marine Corps kicks in with a choral ensemble that leads the singing of the national anthem.  As the anthem’s final notes sound, four U. S. Air Force F-15C Eagles scream overhead.  The sellout crowd roars its approval.

But there is more to come. “On this Independence Day,” the voice of the Red Sox booms over the public address system, “we pay a debt of gratitude to the families whose sons and daughters are ...