When Huey Long was running for office in Louisiana, he told crowds that as a boy on Sunday mornings, he would hitch the family horse to a buggy to take his Catholic grandparents to Mass and then ferry his Baptist grandparents to church. When a surprised friend said, "I didn't know you had any Catholic grandparents," Long replied: "Don't be a damn fool. We didn't even have a horse."

Long was governor and a U.S. senator in the 1920s and '30s, an innocent age when politicians carefully rationed their lies, dispensing them for specific purposes and striving to keep them believable. He might find himself unable to function in the era of Donald Trump, who churns out fiction nonstop with no rhyme, reason or restraint.

Even after two years on the political stage, Trump continues to outdo himself. His penchant for lies resembles an incorrigible alcoholic's thirst for drink: He lives for the next one and can't abstain, no matter what it costs him.

He lies about inconsequential things. After a much-criticized appearance at the Boy Scouts of America's national jamboree, Trump claimed, "I got a call from the head of the Boy Scouts saying it was the greatest speech that was ever made to them." The organization denied it, and his press secretary acknowledged the call never happened.

He lies about consequential things. In tweets announcing his ban on transgender members of the military, he said he made the decision after consultation with his "generals and military experts" — but it came as a surprise to the Joint Chiefs of Staff.

Trump lies about big things, inviting prosecutorial scrutiny. When it was reported that Donald Trump Jr. met last year with a Russian lawyer, Trump Jr. issued a statement that later turned out to be deceptive. The president's attorney insisted the elder Trump had nothing to do with it — but after The Washington Post reported he had dictated it, the White House admitted he had "weighed in."

Trump spins falsehoods in public and in private, even when there is nothing to gain. In a phone conversation with Mexican President Enrique Pena Nieto, Trump bragged he had campaign crowds of 50,000, though his biggest was 30,000. He more or less conceded that his vow to make Mexico pay for a border wall was bogus.

The Washington Post's Fact Checker describes Trump as "the most fact-challenged politician" it has ever encountered. In his first six months, it counted 836 false or misleading claims — 4.6 per day.

It's enough to make me nostalgic for when the White House was occupied by the notoriously slippery Bill Clinton, whom one political rival described as "an unusually good liar" — before Monica Lewinsky. Clinton must be thinking he could have gotten away with more deceit than he dared.

David Corn's 2004 book was titled "The Lies of George W. Bush." A sequel for Trump would take several volumes.

Barack Obama was condemned for what PolitiFact named the 2013 Lie of the Year — "If you like your health care plan, you can keep it." Obama admitted he was wrong and expressed regret. Trump utters bigger lies than that every day and never takes responsibility.

Dan P. McAdams, a psychology professor at Northwestern University who last year wrote an article for The Atlantic assessing Trump's personality, tells me he expected him to greatly curtail his lying once in office. "But no way," he says. "Almost everything that comes out of his mouth now is either misleading, a gross exaggeration or a baldfaced lie."

How does he explain Trump's habit? "What is true for him is what works in the moment to give him a win," says McAdams. "He must win every moment."

But this type of winning doesn't last. Trump's incessant dishonesty has helped drive his approval rating lower than any president's six months in since polling began in the 1940s. It has intensified suspicions about his Russian connections, which are under investigation by a special counsel.

The problem is not just that Trump is defrauding his followers. It's not just that if he has to answer questions during a criminal investigation, he may risk committing perjury. In a war, terrorist attack or other crisis, it's vital for the president to have some credibility with the citizenry.

Trump won't. If and when that moment arrives, most Americans will assume they are being misled. Trump will then find that his habit of lying has made him a loser.

Steve Chapman blogs at http://www.chicagotribune.com/news/opinion/chapman. Follow him on Twitter @SteveChapman13 or at https://www.facebook.com/stevechapman13. To find out more about Steve Chapman and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.