My American Heritage dictionary defines the term “lie” thusly: “a false statement deliberately presented as true.”

That’s a commonly accepted description of a lie. Someone has to knowingly say something that is false.

Well, in politics, lying takes on a different sort of meaning.

Liz Cheney, the daughter of former Vice President Dick “Prince of Darkness” Cheney, said just the other day that President Barack Obama lied when he made grand promises about the Affordable Care Act.

http://thehill.com/blogs/ballot-box/senate-races/190496-liz-cheney-no-question-obama-lied-about-o-care

“No question” that he lied, said Cheney. What’s more, the former VP’s daughter has accused Republican U.S. Sen. Mike Enzi of Wyoming — whose seat Cheney wants to take from the incumbent — of enabling the president to lie about the ACA.

I won’t get into whether Enzi enabled anything.

I am puzzled, though, why we allow politicians to use terms like “liar” and “lie” when the universe could contain all kinds of reasons for untruthful statements.

Yes, the president said anyone could keep their health plans if they wanted to do so once the ACA kicked in. It didn’t happen; millions of Americans had their policies canceled, forcing the president to announce this past week that insurers could keep policies in force for another year.

Pardon the verbal parsing, but for Cheney — who’s an underdog in her campaign to beat Enzi — to suggest that Obama “lied” is to become a mind-reader. She knows without a doubt, she says, that the president lied — which is to say he deliberately stood before the nation and said something he knew to be untrue.

Just maybe the president believed what he said at the time to be true. If someone says something in good faith — believing they are telling the truth — does that make them bad-faced liars?

Here’s an example that might hit Liz Cheney right in the gut.

Her dad told us that the late Iraqi dictator Saddam Hussein possessed weapons of mass destruction. Those WMD became the basis for us launching a full-scale war against Iraq in March 2003. Our troops stormed into Baghdad, captured Saddam, scoured the country from top to bottom looking for those WMD.

They weren’t there.

Did Daddy Cheney tell a lie? I’m guessing his daughter Liz would say “no.” Some of us likely would beg to differ. Hey, that’s politics.