We may never know whether Donald Trump’s dust-up over immigration this week with Pope Francis hurt him or helped him in the South Carolina primary. Anti-Catholicism was once widespread in the deep south, and hints of it may or may not remain.

But the pontiff’s comments about bridges and walls undeniably diverted attention from another nascent conversation that almost certainly would have damaged Trump in the national arena had it had time to flourish.

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The issue was 9/11, specifically who was responsible for crashing the planes into the World Trade Center and the Pentagon. Most people, and the 9/11 Commission, would tell you it was Osama bin Laden’s al-Qaida organization and the 19 terrorists who carried out the mission.

But on Wednesday morning in Bluffton, South Carolian, here’s what Trump said about the topic: “[If I am elected president,] you will find out who really knocked down the World Trade Center. They have papers there that are very secret. You may find it’s the Saudis.”

That’s an extraordinary statement. But within minutes of it beginning to pop up in news stories, the Pope said what he said, Trump responded and everyone began yammering about who was right and who was wrong on the issue of walls.

But hold on a minute. Can we go back to what Trump just suggested?

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The leading Republican candidate for president just insinuated that the Saudi government, a staunch American ally, might have been involved in the planning of the largest terrorist attack on U.S. soil. This just days after he made the charge — he has still not fully rescinded it — that President George W. Bush knew that Iraq had no weapons of mass destruction before the start of Operation Iraqi Freedom, and that he lied about it to the American people to start the war. (Historical footnote: 550 metric tons of yellowcake uranium — the first step toward higher-grade uranium — was discovered and removed from Iraq in the spring and summer of 2008.)[LINK]

Trump, who has made a career out of dropping rhetorical bombs and then walking away from the damage, should be forced to elaborate on his theories in public. In fact, nothing could be more important at this moment in the Republican presidential campaign.

Trump’s not running to be loudmouth in chief; he’s running to be commander in chief, and if he harbors a belief in his mind that 9/11 was some type of massive cover-up, he has a duty to expound on it. If he has evidence that the “9/11 Truthers” have been right all along, let’s hear it.

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The remaining Republican candidates in the race might even want to step away from their podiums at the next debate and give The Donald an open mike.

What he would say might be illuminating, indeed.

William F.B. O’Reilly is a Republican consultant.