So what did Key see over Fort McHenry that fateful night in 1814?

At the time, Key was held on a British ship in the harbor, having arrived there to negotiate the release of American prisoners. Because he was aware of the size of the British fleet, he was not permitted to return to the American lines, forcing him to watch the bombardment of Fort McHenry from afar.

“From the ship he would have seen direct fire from broad guns, which were not explosive,” Porfert says. These were the cannons on the sides of the British ships. There were also British mortar schooners, firing ten-inch explosive rounds at the American position. He would have been able to see the mortar fuses shooting through the sky and the shells as they exploded—surely many exploded in the air before reaching their mark.

Another visually stunning type of weapon was in use that night: a “carcass” round. An explosive mortar shell wrapped with incendiary material, this round was fully engulfed in flame after being fired, streaking through the air before exploding.

“This whole thing was on fire all the way through the sky,” Porfert says. “There was definitely quite a bit of fire and smoke in the air over the fort.”

Although somewhat exaggerated from Key’s original description, modern fireworks displays indeed bear similarities to antiquated munitions used in battles over U.S. soil and are an important part of culture worldwide.

“Fireworks are still using black power, which throws a lot of sparks and smoke, unlike modern smokeless powders,” Porfert says. “When the Chinese made them, they were designed for big aerial displays.”

And that’s exactly what they’re used for: this year, Macy’s Fourth of July Fireworks in New York City will consist of more than 40,000 fireworks synchronized to a 25-minute musical score—and the whole thing is directed by Usher.

If I recall the War of 1812 correctly, there were both rockets red glare and bombs bursting in air.

Wait, did you say directed by Usher? Really??

Hop that flight!

Naw, no fireworks are worth flying cross country for. Not even Usher fireworks.