Manifest Destiny is one of those 19th-century concepts — like the Monroe Doctrine that helped keep our hemisphere free of European and Asia predators for two centuries — that became dangerously unfashionable among the America-hating lefties who long-marched through our institutions.

It must have been 30 years ago that I went to see a Thomas Jefferson impersonator who either quoted or paraphrased Jefferson's thoughts that Americans would need several hundred years to fill in the continent from sea to shining sea. That would have been around 1800. Not quite 50 years later, we welcomed California into the union and went about the serious business of filling in the expanse and closing the frontier — a mission accomplished in 1893, according to historian Frederick Jackson Turner.

A year or so prior, I had a conversation somewhat along this line with a coworker of mine in San Francisco. Scott was a good guy, very sharp — Boomer, Air Force vet, gay but not queer, Democrat but not radical — we'd bonded over our mutual love of bad horror movies and anti-PC politics. This was just two years after the dissolution of the Soviet Union when Mother Russia was at her lowest ebb. Scott suggested to me that we buy Siberia. "Americans do better when we have a frontier," he said not at all joking, "and Russia needs the money."

I told him — again, not at all joking — that the whole thing would be "strip malls from end to end within 50 years."

Americans lost something when we closed the frontier… something very American. The frontier challenged us, sometimes killed us, and its untamed geography helped make us the no-bulls**t, freedom-loving people we are, or at least aspire to be. I wonder sometimes if it's no coincidence that the only uniquely American form of statism — progressivism — took root in the national psyche just as we ran out of new worlds to conquer.

With nothing to tame, it's as though we started trying to tame one another, instead. "SAD!" as POTUS 47 might say.

Well, there's a new world to conquer, courtesy of Elon Musk's ambition to take humanity to Mars.

Make no mistake, SpaceX is going to Mars with or without the imprimatur of the United States of America. But by promising to "plant the Stars and Stripes" on Mars, Trump reminded us that Manifest Destiny is not dead, that there are still frontiers to tame, and most importantly, that Americans are still capable of great daring.

Like our British cousins before us, I'm certain that any control we enjoy over our Martian colonists will be both tenuous and short-lived. And that's OK because America is an idea, an idea already carved into (and forged from) one new world and, someday sooner than many reading this today would believe, perhaps another.