Jane Fonda should have been charged with treason for her flag-bashing trip to Hanoi during the Vietnam War!

The Oscar-winning actress is just as guilty of betraying America as Taliban rat John Walker — the California man who joined Osama Bin Laden’s terrorist network and is now behind bars, declares a well-respected law professor.

“Jane Fonda has become an American icon. But to me, she’s one of the most reprehensible Americans living today,” Henry Mark Holzer — professor emeritus at New York’s Brooklyn Law School — told The ENQUIRER.

“What she did during the Vietnam War was appalling. She should have been indicted for treason.”

In July 1972, at the height of the Vietnam War, Fonda created a firestorm when she visited the North Vietnamese capital of Hanoi and was photographed at the controls of an antiaircraft gun used to shoot American fliers.

“While she was in Hanoi, Fonda made at least six propaganda radio broadcasts condemning the United States,” said professor Holzer, coauthor with his lawyer wife Erika of the book, “Aid and Comfort: Jane Fonda in North Vietnam.”

“She said American pilots were bombing nonmilitary targets like hospitals, villages, schools and factories. But that was simply not true!

“She said American troops were fighting for big companies like Esso, Standard Oil, Shell and Coca-Cola — and that we shouldn’t be on the side of those murdering innocent people.

“She also met with Communist leaders, called them her friends and said she was honored to be a guest in North Vietnam.

“Then she encouraged South Vietnamese troops to desert and join their North Vietnamese countrymen. These are not the acts of an American icon, but the acts of someone who should have been indicted and convicted of treason!”

Fortunately for Fonda, she was never charged with treason — which carries a mandatory death sentence — because of the political climate at the time.

“President Nixon was running for reelection and trying to end the war,” Holzer pointed out.

“It was felt that putting Jane Fonda on trial would become a circus, which was the last thing the Noxon administration wanted.

“But if she had been charged, I feel a jury would have convicted her.”

While there’s no statute of limitations on treason, Fonda will continue to go unpunished, he says.

“From a practical point of view, it’s too late to indict her now.”

Like Fonda, there is “absolutely” enough evidence to charge Taliban rat Walker with treason, Holzer says.

Instead, Walker has been charged with 10 felonies, including plotting with terrorists to kill American soldiers in Afghanistan. If convicted, he faces a maximum penalty of life in prison without parole.