One would have thought — at least I did — that the birther issue that dogged Barack Obama for his entire first term as president would have ended when he got re-elected in 2012.

Silly me. What was I thinking?

Now we have another presidential candidate with a citizenship issue to resolve — in the eyes of some.

It’s getting complicated.

Ted Cruz is the problem. Why?

Well, the junior U.S. senator from Texas in fact was born in another country … Canada, to be exact. His mother is an American; dad is a Cuban. But the Republican presidential candidate’s citizenship has been resolved because of his mother’s heritage. The Constitution only requires that one parent needs to be a citizen in order to qualify someone to run for president.

That didn’t matter with critics of President Obama, whose late mother also was an American. He was born in Hawaii, one of our states. He has produced a birth certificate that confirms what he has said all along.

Then someone stood up in a New Hampshire town hall discussion the other day and declared that Obama is a foreign-born Muslim.

Donald Trump, another GOP presidential candidate, was running the meeting. He didn’t come to the president’s defense on that nonsensical statement.

Why not? Well, according to some, Ted Cruz’s presence on the national political stage complicates it for Trump.

If he comes to Obama’s defense, then he all but admits his own questioning of the president’s constitutional eligibility was a sham. If he defends Cruz, then that, too, eliminates his own ridiculous doubts about whether Barack Obama was qualified to hold the office to which he’s been twice elected.

Ted Cruz is qualified to run for president. Barack Obama is qualified to hold that office.

Politicians have apologized in the past for making false statements … haven’t they?

Isn’t it time for Donald Trump to come clean and admit he, um, made a mistake?