America’s foremost humorist, Mark Twain, considered the Spanish-American War ironic. (Actually he considered it borderline criminal.) Our forefathers had come to America to escape tyranny and yet we became imperialists.

If Twain had lived during McCarthy’s era he’d have likely been hauled before the Un-American Activities Committee. Can you believe there was ever such a committee? Or that Americans of Japanese ancestry were sent into internment camps? Sadly, under similar circumstances, we’d probably do it again.

Consider that George Washington strongly warned us against “foreign entanglements.” But for over a century now we’ve been tangling all over the globe. About every 20 years we often wage pointless wars as the self-appointed world’s policeman, sacrificing our young and our treasury. (I can hear a reader ask, “And your point is?”)

As opposed to the bogus rationales of “Remember the Maine,” or “WMDs,” we enter these wars for power, money and for that hideous black crude called oil (which, I believe is a lyric of the opening to “The Beverly Hillbillies”).

Contrary to Hollywood’s version, our record with the Native Americans was shameful. While the British Proclamation of 1763 forbade colonists from settling west of the Appalachians, after our independence, we decimated the Native Americans. (Later we’d give what’s left of them casinos.)

According to University of Colorado studies, the Native American population went from an estimated 12 million in 1500 to 237,000 in 1900. I’d call that genocide but I don’t want angry e-mails from John Wayne fans.

Our justification was “Manifest Destiny,” the 19th century belief that God had ordained it that we should expand across the continent. (As the Church Lady from “Saturday Nite Live” said many years ago, “How convenient.”)

I mention all of this because last month, after almost nine years, our combat troops finally came home from Iraq. (ABC news calculates the Afghan War is the longest in our history, Vietnam second and Iraq a close third.) But a few days after we left, 63 Iraqi civilians were blown to smithereens in terrorist bombings. Lovely.

So I thought I’d tally up the pluses and minuses of the Iraq War. But first please remember that we still have a significant presence there, our embassy. (And we somehow own the land, so it’s rent-free.)

Our Iraq embassy is the most expensive in the world ($750 million to build and $1.2 billion a year to operate). It’s bigger than the Vatican. It’s bigger than 80 football fields should we run out of venues to hold the Super Bowl. (I just hope that the embassy is fortified to withstand angry Iraqis when they eventually storm the joint.)

As for the cost of the Iraq War (some call the worst foreign policy blunder in our history) it’s estimated between $3 trillion and $5 trillion by the time we treat the wounded soldiers, many of whom are permanently disabled — 4,487 GIs died and 32,226 were wounded.

But the wounded numbers don’t include the 300,000 brain injuries, or the tens of thousands of PTSD cases. Meanwhile, 18 vets commit suicide daily and more than 135,000 are homeless. It’s a sad commentary we seem to forget.

We did get rid of Saddam but in so doing we made Iran, part of Bush’s “Axis of Evil,” the dominant power in the region. Having feared Saddam for decades, the Iranians must thank Allah we did them this “generous” favor.

Frankly, I don’t see any pluses from the Iraq War for our citizens. But corporations like Halliburton, Blackwater and especially BP (polluter of the Gulf Coast) and Exxon, with Iraqi oil refinery contracts for trillions of dollars, made out like bandits. (Actually an apt analogy.) For those who predicted it would help the price at the pump, when Clinton left office gas was $1.39 and now you need a second mortgage to fill your tank.

Vietnam was another sad chapter. As early as 1965 LBJ admitted (revealed via taped phone calls) that he saw no way we could win the Vietnam War. It took eight years and 58,000 GI deaths to get the same peace settlement that was on the table back in ‘66. In Vietnam we invaded a country whose culture and history we didn’t bother to understand.

In 2003 we invaded Iraq with seemingly no awareness that Sunnis and Shias have been fighting each other since 632 A.D. Frustrated, Bush even said, “I just don’t get it, they’re all Muslims, aren’t they?”

Lately I often think of the Roman Empire. It began as a democratic federation of independent farmers. Over time the Senate wastefully sent Roman legions all over the world. The rich became even richer but the Republic was replaced by an Empire doomed to fall. I suppose we’re following the adage, “When in Rome do as the Romans.”

Will we ever learn? We haven’t so far.

Jack can be reached at Jnsmdp@aol.com.