Smyrna, Tennessee — Ralph Bristol, Nashville, Tennessee’s talk radio king, says the Second Amendment gives Americans their best, last line of “homeland security.”

He’s taking that message on the road in his back-of-the-truck tour “to get those who are licensed to carry – to carry.”

“They’ve already enlisted by getting licensed to carry,” Bristol tells Breitbart News. “I just want to make sure we all understand ‘we’re on duty,’ so don’t leave your equipment at home. And, it’s to teach the public in general why they should embrace us, not fear us.”

Bristol says his “12 stop tour” began modestly, but is gaining momentum as his message resonates with Americans who realize Islamist enemies intend to “change the rules of war” and attack civilians in their homes and businesses on this side of the Atlantic.

The radio host tells Breitbart News he needs about 30 minutes to explain, in detail, why Americans should arm themselves so they are prepared in the event they find themselves in the middle of an attack by a radicalized Islamist. He cites two recent examples: the murders of four Marines and one sailor by a radicalized young Muslim in Chattanooga, Tennessee, and the successful disarming of an Islamist terrorist by three young American tourists on a train in Europe.

That’s too long to do in his fast-moving morning talk show, Bristol says, so he decided to take his message on the road.

Fifteen people attended the first stop at the Hermitage Library in Nashville last month. Fifty four attended his second stop in Clarksville, Tennessee. On Saturday, the crowd grew to 150 when his back-of-the-truck “The 2nd Amendment IS Homeland Security” tour stopped in the parking lot of the Legends Steakhouse in Smyrna, Tennessee.

Each tour stop adds a new element. Saturday’s stop included the public debut of a moving song about the 9-11 terrorist attacks, as seen 14 years later by a man who was a teenager when the attacks took place, written and performed by Nashville recording artist Adam Pope, “Ain’t Over It Yet.”

Bristol tells Breitbart News how the idea for the tour came to him.

He was travelling through Nashville rush hour traffic at about 5 mph at 5 p.m. on Friday, July 17, 2015, when a wave of grief for the families of four Marines and a sailor, gunned down in Chattanooga, TN a day earlier, washed away the solitary pity party he was hosting in his truck, on the way to be the keynote speaker for the annual Hickman County, Tennessee Reagan Day Dinner.

Ralph had accepted the invitation to speak at the dinner months ago, and had written his speech at least a month earlier, on the “moral imperative of tax reform.” U.S. Rep. Marsha Blackburn (R-TN) would introduce him, and he had audiences that would listen to him for longer than the maximum “speed date” conservation than he can have with his radio guests and audience, between 5 and 9 a.m., where he does the morning drive talk show on Supertalk 99.9 WTN.

He knew his speech in Lyles, Tennessee – about an hour and 30 minutes (in good traffic) from Bristol’s Donelson, Tennessee residence – would take him through the belly of the Nashville traffic beast at the at the same time his great-granddaughter, one-year-old Olivia, would be arriving from Missouri at Bristol’s Tennessee home with her parents, Amber and Connor, Bristol’s granddaughter and grand-son-in-law, at the same time he would be stuck in the belly of the beast.

“Giving in to selfishness,” as he later called it, Bristol was focused on the fact that he would be speaking after his normal bedtime (he’s up at 1:30 each morning), and that he couldn’t be home when Olivia arrived (not to mention being stuck in traffic) when the first wave of grief for others hit hard.

It had begun to build much earlier. After Bristol signed off the air Thursday, 24-year-old Muhammad Youssef Abdulazeez crashed his car through the gates of a naval training center in Chattanooga and shot and killed four marines and a one sailor. These were five young Americans whose grandfathers, fathers and mothers, and brothers and sisters would never see them again.

The news of the shooting had been extensive all day, as Bristol prepared for his granddaughter and great-granddaughters’ visit, and his speech that night. The one fact that kept gnawing at him is that the military victims were unarmed – because they orders to be. Marines and sailors, facing an enemy, were ordered to be unarmed, and they were. And they were dead.

It was while sitting in traffic that Bristol finally succumbed to the anger and grief as he let himself imagine being a member of one of the fallen Marines’ or sailor’s families.

After drying his tears and fretting those to come, Bristol tossed the blue spiral notebook with his latest speech (still not delivered) in the back seat of his truck and about an hour later, walked into the East Hickman Community Center without a crutch.

When State Sen. Kerry Roberts (R-Springfield), seated beside him at the head table, asked Bristol what he was going to speak about, Bristol answered, “I’m not quite sure.”

“Ralph Bristol unplugged?” Kerry asked.

“Probably,” Bristol answered.

Bristol fought back a few tears and apologized for a few swear words during his talk. For a bit longer than the 20 minutes he was allotted, Bristol unleashed a “Ralph Rant” that was barely premeditated, and a bit raw.

“How can we the people of the United States stand by and allow our leaders to force our fighting men and women to live under rules that require them to face the enemy unarmed? This will not stand! We are going to do something about this!”

The next morning, Bristol posted a “selfie” on Facebook wearing a t-shirt that said “The 2nd Amendment IS Homeland Security” along with a message, “Any questions.”

The picture got a record number of “likes” and dozens of questions: “where can I get that shirt?” The answer was no-where, because it was one Bristol had made years ago, as part of another venture. But the interest in the phrase prompted Ralph to post a second picture – of his two handguns – with the promise, “As of today, in honor of the Chattanooga Five, I’ll never leave home without them.”

Then, because, so many people had expressed an interest in wearing the t-shirt, Ralph decided to create a new speaking tour, during which he would tell people the deeper meaning of the saying, “The Second Amendment IS Homeland Security,” and what it demands of Second Amendment practitioners, the approximately 12 million people in the United States who have gone to the considerable time, trouble and expense to be able to legally carry a gun while in public.

It’s a story that weaves the God-given instinct to survive, both individually and a nation, the recognition of the inalienable right to life, articulated in the Declaration of Independence, the role of weapons in the instinct to survive and the right to life, the role the 2nd Amendment plays in today’s Homeland Security mission, and how it is both different from, and similar to, the original purpose of the 2nd Amendment.

Along the way, Bristol relates memories from his own childhood in Nebraska, specifically that of his World War II veteran father carrying his .32 caliber in response to serial killer Charles Starkweather on the loose in 1958. Martin Sheen played the Starkweather character in the 1973 movie based on his life, Badlands.

That memory, Bristol says, drives his understanding of both today’s challenge and the fears of those who want to limit everyone’s ability to carry guns.

Response to the tour has already exceeded Bristol’s initial expectations, but he thinks each stop will be bigger and better.

So far, his audience has more than doubled at each successive stop.

Breitbart News asked Bristol how large the crowd will be at his 12th and final tour stop, which he anticipates will take place on the 4th of July, Independence Day, 2016.

“Over a thousand,” Bristol responded.

In light of how Tennesseans are responding to his message, Bristol may want to book a larger venue.