It’s an incontrovertible fact that millions of lives were saved because President Harry Truman dropped the bomb on Hiroshima. I know because I’m one of them.

My father enlisted in the U.S. Navy the day he turned 18 in 1945. He finished his basic training as the Allies were preparing for “Operation Downfall” – the code name for the invasion of the Japanese mainland.

Experts predicted it would be ten times bloodier than Iwo Jima. Casualty estimates ran into the millions – for both sides.

Lest we forget, Imperial Japan was a ruthless warrior culture whose war crimes rivaled the Nazis. Surrender was not in their cultural vocabulary. At Iwo Jima, the Japanese fought to the death – literally committing suicide – rather than surrender.

Now imagine how they would have fought for their mainland. It would have been the bloodiest invasion in a long and bloody war.

The War Department had no illusions about this. They ordered the creation of 500,000 Purple Heart medals in anticipation of the casualties.

My dad would have been part of that massive invasion force. God only knows if he would have made it out alive.

God only knows how many other American fathers and grandfathers lived because Harry Truman had the guts to make a tough call.

In fact, God only knows how many Japanese are alive today because instead of firebombing all of their cities and turning them into moonscapes like we did Tokyo, we targeted two. And make no mistake, the death cult gripping Imperial Japan would have forced every non-combatant to fight to the death down to the last man, woman, and child – just like Iwo Jima.

President Truman knew this. He made the moral calculus. He took responsibility for it. The war ended, and we went about the business of rebuilding Japan and Germany.

Does anyone think the Imperial Japanese or the Nazis would have returned the favor had they won the war?

Of course not, but it doesn’t matter. They lost, and we won. And the world is a better place because we’re a moral people. That’s how we roll. Our Greatest Generation reached out a helping hand to their mortal enemies and made them peaceful economic rivals. That’s the beauty of the free market system.

It’s because of the free market – and the free exchange of ideas – that I, a daughter of a World War II vet, drive a Honda. My Sony TV is playing in the background, my Nikon camera is on the bookshelf, and I’ll probably order sushi for lunch.

However, that doesn’t erase the history of what happened. Harry Truman understood that. He lived with the decision to drop the bombs.

Years after he left office, Truman wrote, “I knew what I was doing when I stopped the war that would have killed a half a million youngsters on both sides if those bombs had not been dropped. I have no regrets and, under the same circumstances, I would do it again.”

And yet, here comes Truman’s successor, Barack Hussein Obama, on the eve of Memorial Day weekend to deliver the latest installment in his “Blame America First” Apology Tour.

Barack Obama’s speech at Hiroshima today was another attempt to strip away America’s moral authority. But this time it was even worse. He spat in the face of our fathers and grandfathers.

He dishonored our Greatest Generation by suggesting they’re no better than the butchers who committed the massacre of Nanking, the rape of the Comfort Women, and the Bataan Death March.

There is no moral equivalence between America’s wartime leadership and the totalitarian regime that launched a sneak attack on us that left 3,000 Americans dead. None whatsoever.

There is no moral equivalence between American G.I.s and the death cult that raped and murdered Americans, Chinese, Koreans, and countless of our Allies. None whatsoever.

For an American president to even suggest otherwise is beyond vile. At the bare minimum, it deserves the censure of the United States Congress.

My father, Joseph A. Mansour, passed away in 2002. He was a kind and gentle man, a devout Catholic who went to mass every day and said the rosary every night before bed.

He never cursed and hated it when any of my siblings or I swore. He said he’d heard so much swearing in the Navy, that he never wanted to hear any more, certainly not from the mouths of his children.

But if my dad were alive to hear Obama’s speech today, I think he would allow me this one exception on his behalf:

President Obama, respectfully, go to hell.