Everyone who believes in the spirit of liberty should send a letter of praise to Bernadette Houghton Headd of Macomb Township, Mich.

Actually, you should send her some money. She needs it for bail and legal expenses.

Headd is in jail after an altercation with a pickup truck driver who, if her relatives are to be believed, was trying to run her and her 1993 Chevy Cavalier off the road. Millions of car drivers have had a similar experience in the years since the light-truck fad began. And millions have wanted to do what Headd did: take out a pistol and start shooting.

This got her charged with assault with a deadly weapon, discharge of a firearm from a motor vehicle and using a firearm during a felony. But when the story made national news on the Internet, it also made her a heroine to car drivers all over America.

Ever since this light-truck fad began a decade or so ago, those of us with the taste and good sense to drive cars have been at the mercy of the louts in giant SUVs and pickups. These monstrosities are marketed to appeal to the cretins who wish to bully other drivers. Headd’s antagonist was driving a Dodge Ram, the very name of which conjures an image of the threat she saw in her rearview mirror on that fateful day last month. It happened right after she pulled onto Interstate 94.

Headd was still in the right lane of the three-lane road when she found herself being tailgated by the Ram, said Capt. Tony Wickersham of the Macomb County Sheriff’s Department. Normally, when one of these louts gets on your bumper, you can just move over to the right lane and let him pass. But Headd had nowhere to go and, according to what her relatives told the Detroit Free Press, the 39-year-old mom feared for her life.

As it happened, Headd had at her disposal a pistol that she was licensed to carry. So she pulled into the middle lane and fired a shot — not at the troglodyte in the truck but at his tire. She missed.

The driver then flagged down a sheriff’s deputy who promptly arrested Headd.

“I’m tired of people tailgating me,” Headd told the arresting officer.

I asked Wickersham whether the truck driver was also charged for his role in the incident. He wasn’t.

That didn’t seem fair to me. It didn’t seem fair to James W. Ely Jr. of Vanderbilt Law School. Ely is a member of the Federalist Society, a group of legal experts with a great fondness for the spirit of liberty embraced by the founding fathers in the early days of the republic. Back then, there were no police, Ely told me.

“All you had was a night watch system that was inherited from English common law,” said Ely. “Their duties were mainly to watch for fires and apprehend people in the middle of breaking into houses.”

Other than that, people mainly took care of their own interests.

“If you were in the middle of a holdup, you didn’t have a phone to call the sheriff,” he said. “It was fairly common for people to go armed. You certainly would have had incidents where people thought they were acting in self-defense.”

So imagine a male driving a horse and carriage who tried to run a woman’s carriage off the road. And imagine she fired a warning shot at him. What would have been the legal implications?

“Probably nothing would have happened because it wouldn’t have been reported,” said Ely. “The man might have found some sense of shame in having been fired on by a woman.”

That’s not the case anymore. The people who buy these trucks like to think of themselves as tough guys — until someone throws a little lead their way. Then they go running to the cops like little boys running to their mommies after picking a fight and losing it.

In the good old days, the sheriff wouldn’t have been so sympathetic, said Ely. If the man had filed charges against the woman, she could have hit back with charges of her own. A grand jury would have sorted it out.

These days, the cops take sides. They don’t enforce the laws against tailgating, but let a little lady even the odds a bit, and all of a sudden the sheriff discovers a need to enforce the law.

Call me old-fashioned, call me a traditionalist, but I long for the old days. You come at me with a Ram, I come back at you with a Colt.

That is the spirit of liberty, and if it were still alive in the land today, Bernadette Houghton Headd would be a free woman.