So help me, I was certain that Donald Trump sank his presidential campaign when he made light of John McCain’s heroic service during the Vietnam War.

It didn’t happen.

I was certain that he would implode during that first Republican joint appearance with nine other “leading” GOP candidates.

That didn’t happen, either.

Then he got into that public feud with Fox News anchor Megyn Kelly over that ghastly remark he made about the source of “the blood.”

Hey, no problem.

Trump said “I’ll build a wall” to keep illegal immigrants from entering the U.S. through its southern border. Yep, he’s going to do all this all by his ownself.

I don’t pretend to be an expert on this stuff.

The latest poll numbers show that Trump is putting some distance between himself and the rest of the GOP field — which comprises some serious, intelligent and accomplished individuals.

What in the world is happening here? Have we become so celebrity conscious that we (meaning the Republican Party’s most faithful voters) place celebrity above actual knowledge of things, such as, say, the limits of the office at stake?

Trump is sounding like someone who wants to take singular control of the federal government. All those first-person singular references to all the action he intends to take suggest he doesn’t understand that the U.S. Constitution inhibits the power of the presidency.

Checks and balances, Donald?

The current president, Barack Obama, has used his own executive authority rationally and in accordance with the law … and yet we keep hearing from GOP leaders about the “lawlessness” they insist pervades the Obama administration.

Just wait’ll they see what a President Trump might try … not that it’ll matter to them.

And yet the man continues to set the pace in a field of highly qualified GOP contenders.

What in the world gives?