On the eve of the Fourth of July, Washington lay beneath a heat dome that pushed temperatures past 100 degrees Fahrenheit, the air thick and unmoving. Russell Dickerson, a chemistry professor at the University of Maryland, looked at the forecast and decided he would not take his grandchildren to the National Mall. “I don’t think it’s wise to shoot off 850,000 fireworks on a hot, windless, polluted day,” he said. Across town, Adrian Aceves, a medical resident, prepared a sedative for his five-year-old dog, planning to stay home as the sky erupted.

The display itself, branded “Freedom250,” is designed to be the largest in history. Organisers have contracted the Pennsylvania firm Pyrotecnico to launch more than 850,000 shells from ten sites around the Lincoln Memorial and the Potomac River, beginning at 10:30 p.m. and lasting forty minutes. That is roughly 40,000 more than the current Guinness World Record, set in the Philippines in 2016, and fifty times the scale of the capital’s usual annual show. Nearly two thousand kilometres west, at Mount Rushmore in South Dakota, a separate fireworks event was planned for the same weekend—the first there in six years—despite a persistent drought that has left much of Pennington County in moderate to extreme dryness and prompted the Sierra Club’s local chapter to call the idea “a very bad idea.” State and federal officials said a final decision on whether to proceed would be taken on the day itself, based on fire-risk conditions.

The pyrotechnics are the centrepiece of a broader, Trump administration-driven celebration of the 250th anniversary of American independence, an undertaking that has blurred the lines between civic festivity and political rally. A “spectacular TRUMP RALLY” was scheduled for 9:45 p.m., just before the fireworks. The month-long America250 festival on the National Mall, run by an events company founded by former Trump aides, has been marked by weather shutdowns, technical difficulties and the withdrawal of most scheduled musical performers, some citing unease over the event’s partisan tone. The funding picture remains opaque: the White House has not disclosed the cost of the Pyrotecnico contract, while a separate $1.5 million payment to a different fireworks company, Garden State Fireworks, far exceeded the roughly $300,000 paid in previous years. Reporting by The Independent found that $90 million was being diverted from a National Parks Service fund intended for park repairs, and an estimated $68 million in taxpayer money was channelled to the festival through a nonprofit with limited transparency. At the Kennedy Center, a “Presidential” rooftop viewing package was offered for $25,000, accommodating up to thirty-six guests.

Viewed from the perspective of public health researchers and environmental scientists, the scale of the display raised distinct alarms. Glory Dolphin Hammes, head of the North American arm of the air-quality firm IQAir, described the expected pollution levels as “apocalyptic.” Data compiled by the company showed that on 4 July 2025, fine particulate matter (PM2.5) peaked at 133 micrograms per cubic metre—nearly four times the U.S. Environmental Protection Agency’s 24-hour exposure limit—pushing the air quality index to 208, a figure more commonly associated with cities in South Asia. Dickerson noted that without rain to clear the air, the smoke and pollutants could linger for hours, exposing crowds to “massive amounts” of fine particles capable of penetrating the lungs and bloodstream. Animal welfare groups and pet owners voiced parallel concerns: a recent European study found that migratory birds disturbed by New Year’s fireworks abandoned their resting sites and never returned, while in Washington, veterinarians braced for a surge of sedated and anxious dogs.

At Mount Rushmore, the debate carried a longer historical echo. A 2016 U.S. government study had detected perchlorate, an oxidising agent used in fireworks, seeping into the groundwater near the monument after years of Independence Day displays. As the weekend approached, the only certainty was that the smoke would hang in the still air long after the last burst of colour faded, and that the perchlorate already in the soil would remain, invisible and slow to disperse.