Jimmy Carter once promised that he would never lie to Americans if they elected him president of the United States.

To the best of my knowledge and memory, the 39th president kept that promise. Perhaps he didn’t tell us everything in real time about sensitive negotiations with Egyptian President and Israeli Prime Minister Menachem Begin as they crafted a comprehensive peace treaty. He might have held back on what he told Iranian leaders who held our citizens hostage for 444 days in 1979-80.

I don’t believe he lied.

We fast-forward now to the present day. The current president has demonstrated that he cannot tell the truth.

Donald Trump lies at every level. He lies when he doesn’t need to lie. He lies when it is easier to tell the truth. He lies about matters large and small.

I cannot single out the major lies he has told. They usually involve a political foe. He will say something that puts someone in a negative light. If it’s a lie, well, so be it.

The petty lies are equally remarkable. He lied about his late father being born in Germany; Fred Trump was born in New York City. He lied about losing friends on 9/11; he lost zero friends, he attended zero funerals of those who died on that terrible day.

Trump is lying at an astonishing pace. The Washington Post is keeping a running tabulation the falsehoods; it has passed the 10,000 mark so far and the pace is quickening.

I mention all of this because Donald Trump keeps insisting that he has been “totally exonerated” regarding the Russia matter. No, he hasn’t.

Thus, Trump lies even when the public record demonstrates precisely the opposite to be true. Robert Mueller’s report on his investigation into alleged collusion is clear: The special counsel could not clear Trump of obstruction of justice; nor could he prosecute him. Still, Trump lies when he says he has been “totally exonerated.”

How in the world can we accept a single thing this individual says as truth? My view: We cannot.