Branding a candidate “flip-flopper” can be the kiss of death for a campaign. But maybe the world doesn’t need fewer flip-floppers. Maybe we need more of them. Yes, you’re supposed to hate them. It’s supposed to be a sign of a faulty character.

But flip-flopping can be a good thing. Our best presidents did it. Our best candidates are doing it now.

Take health care overhaul and the individual mandate, which snares a good portion of both sides of the presidential fields of the two most recent elections in what could arguably be called a flip-flop.

Barack Obama ran for president opposing a requirement for Americans to buy health insurance. But that didn’t stop him from signing one into law. Mitt Romney also signed an individual mandate into law, but as governor of Massachusetts. He now supports repealing the national mandate President Obama signed into law nationally.

Newt Gingrich also supported an individual mandate in the 1990s as an antidote to the Clinton health plan. When Obama was opposing the individual mandate, it was against then-Sen. Hillary Clinton, who was running for president and supporting the very thing Gingrich had once used against her.

“Flip-flopper” as a derogatory term was perhaps most effectively used against Massachusetts Sen. John Kerry, who was targeted for his position on a war-funding bill. “I actually did vote for the $87 billion,” he said. “Before I voted against it.”

He was referring to different versions of the war-funding bill in question. But no matter. “Flip-flopper” endangered his political brand and it has been in heavy use ever since.   Read more about Kerry’s 2003 reversal.

And there are some notable flip-flops that did not work out. President George H.W. Bush inviting people to “Read my lips. No new taxes.” When he ended up raising taxes anyway, it angered his base. He didn’t win re-election.

To be called a flip-flopper is, at its core, to be called someone without character. And character is perceived as an essential presidential attribute. “Character is the only secure foundation of the state,” Calvin Coolidge famously said.

Richard Nixon, who was ultimately undone amid the baring of his own character, said, “With all the power that a president has, the most important thing to bear in mind is this: You must not give power to a man unless, above everything else, he has character. Character is the most important qualification the president of the United States can have.”

Read “It’s the Values, Stupid: Why Character Counts in 2012? by ABC News contributor Matthew Dowd.

But there’s also a compelling argument that a president needs to be able to flip-flop when the need arises.

History has some notable flip-flops that today are lauded as the right thing to do.

For starters, Abraham Lincoln was elected to office in 1860 as a candidate promising to keep the union together rather than end slavery. He wanted to take a more incremental “compensated emancipation” approach, rather than declaring emancipation, which is what he did in 1862. Historians still argue about his thoughts at the time, but it’s clear that he came into office pledging to do one thing and ended up doing something quite different.

The same could be said for Thomas Jefferson, who figured Spain would gradually lose control of lands west of the Mississippi. But when much stronger France took control of the land from Spain, he pledged to take up with the United States’ traditional enemy, Britain, and ended up buying the land, and putting the United States in monetary debt to Great Britain.

Franklin Roosevelt pledged in 1940 that if he were re-elected, the United States would not become entangled in foreign wars. But after Pearl Harbor about a year later, the United States most certainly did.

“These are great big important things to flip-flop on,” sauthor and ABC News analyst Cokie Roberts said. “I think it makes all the sense in the world to learn and to say situations have changed  and not this is what’s called for. To lock yourself in stone in some position that’s the wrong thing to do makes no sense at all.”

But there is certainly a distinction between a politician changing his or her mind in office as opposed to changing to get to office. “Flip-flopping to get to office is a bit like a deathbed conversion,” Roberts said.

Opponents of Mitt Romney and Herman Cain in the current Republican presidential field have sought to brand the men “flip-floppers.”

Both candidates have reversed policy positions.

Read about Mitt Romney’s reversals.   Read about Herman Cain’s.

“If you don’t change in the private sector, you look stubborn,” Romney said at a town hall meeting in New Hampshire. “It’s what Winston Churchill said, if the facts change, I change, too. But I’ve been in the private sector, I know how jobs work and I took that and applied to the Olympics scandal and got them back on track and then applied to the Massachusetts legislature, where there are a lot of Democrats. ”

A report by NBC suggested that quote was not Churchill’s but actually by John Maynard Keynes, the business economist now reviled by many conservatives who disdainfully say “Keynsian economics” has failed the United States.

Cain has said it’s human to make mistakes and he’s not the kind of guy who is not going to admit it.

“The thing that’s going to convince people that my campaign is credible is if I make a misstatement, I’m going to retract it,” he told reporters in Chicago this month. “If I make a mistake, I’m going to admit I made a mistake. The last perfect person was hung on a cross 2,000 years ago.”