Every few minutes cars and vans turn off a lonely stretch of highway, drive up a gravel road, and park in front of some brightly colored tents.
Their occupants go in, buy the merchandise and exit, paper bags in hand, with contraband.
Well, not exactly contraband.
The firecrackers and bottle rockets sold by Fireworks City and Captain Jim's Fireworks are perfectly legal here in Missouri. But transporting them a few miles up the road, across the Mississippi River into Illinois, is breaking the law.
Which poses an intriguing dilemma for border cities and towns all over the United States. In the battle against crime, just how criminal are small-scale street fireworks?
And what about Independence Day? Shouldn't the "Home of the Free" let its citizens celebrate with a bang if they want to?
The answer, it turns out, depends exactly which piece of the Home of the Free you occupy. Some 32 states allow some or all fireworks, while 10 ban everything, and six others look askance at everything but sparklers. Hundreds of cities and counties also have their own ordinances.
And even where the devices are illegal, enforcement varies. They draw scarcely a sparkle of interest in some jurisdictions while in others, they're causing an explosion of activity.
Take greater Washington.
In the city itself, you can buy all the fireworks you want. But just across the border in Maryland, only sparklers are allowed. So, every year on the week before Independence Day, the Montgomery County, Md., fire marshal's office mounts its fireworks abatement program. It's a serious campaign. The marshal sends unmarked cars into Washington, to keep an eye on fireworks dealers near the border.
"We're looking for Maryland tags," says Brian Geraci, assistant fire marshal for the county. Officers follow Maryland cars discreetly. When they cross into Montgomery County, they stop them, confiscate the fireworks, and urge the occupants to see a public fireworks display instead.
On the whole the public has responded positively, Mr. Geraci says. "We've been trying to be more friendly."
So is Massachusetts. Every year before Independence Day, the state's department of fire services has invited reporters to see how it's cracking down on illegal fireworks. With the help of officers in New Hampshire (where fireworks are legal), Massachusetts cars parked at border fireworks vendors were stopped when they crossed back into Massachusetts and the fireworks confiscated. But the practice stirred some controversy in the Bay State. This year the department has changed tactics, keeping mum about its enforcement campaign and instead this week set off fireworks next to plywood figures in Boston to show how dangerous they are.
In fact, safety is the major reason state and local authorities take such a hard line against fireworks. Last year, the explosive devices caused some 8,300 reported injuries and thousands more that went unreported, many of them to children. Even a sparkler can reach 1,200 degrees.
"People don't understand that fireworks are almost temperamental," says Jennifer Mieth, public-education manager for the Massachusetts Department of Fire Services. "We're still engaging in a very comprehensive education and enforcement series of activities. We're just not doing it in as a high-profile way as in the past."
It's hard to get more low-profile about fireworks than Alton, Ill., the first Illinois city after Captain Jim's Fireworks here in Missouri.
"The state has a law against it, but it's not strictly enforced," says Vernon Henley, deputy chief for the Alton police department. Officers will respond if neighbors complain about noise, he adds. But "we don't have roadblocks set up for the bridge" to Missouri.
Stepping out of Fireworks City in Missouri with a bag of goodies, Illinois residents Marc and Anita Eyer don't worry about a fireworks crackdown. "We buy them every year," Mr. Eyer says.
But don't try that in Liberty, Mo., which has made fireworks possession a crime. At first, local police issued warnings when they confiscated fireworks. But starting last year, police have taken to handing out citations, which work much like traffic tickets.