Before Donald Trump arrived in Washington with his lowered standards and upended norms, one of the worst sins you could commit in American politics was to become known as a "flip-flopper."

You remember the presidential election of 2004, right? John Kerry offered a stiff challenge to the incumbent, George W. Bush, but ultimately lost a close campaign. One of the things that did Kerry in: A reputation for fecklessness, supported by his defense of a vote against Iraq War funding — "I actually did vote for the $87 billion before I voted against it."

It was a moment the Bush campaign used to devastating effect, relentlessly airing a commercial that showed Kerry on a sailboard, drifting along the waves — first to the right, then to the left, then to the right, then again to the left. "John Kerry," the announcer intoned. "Whichever way the wind blows." Kerry never quite recovered.

How times have changed.

On Tuesday, President Trump announced via Twitter that the United States would not be re-entering the Trans-Pacific Partnership, a trade pact with 11 other countries, including Japan, Australia, and New Zealand. "I don't like the deal for the United States," Trump wrote.

Trump's announcement was a change of position from the previous week, when he directed his top trade and economic advisers to take a fresh look at the TPP, offering hope to trade advocates that he might be ready to cut a deal. And that position was a reversal of one of his very first acts in office — withdrawing the United States from trade treaty it had spent years helping craft.

Flip. Flop. Flip.

"The president is a guy who likes to ... entertain a lot of different ideas," Sen. Ben Sasse (R-Neb.) said, testing the limits of understatement.

That's not even the Trump administration's only reversal this week: Witness the infighting that resulted when U.N. Ambassador Nikki Haley publicly announced that the White House was prepared to impose harsh new sanctions on Russia. The rug was quickly pulled from under her: Trump was reportedly enraged by her announcement. Another administration official suggested Haley had been "confused.”

”With all due respect, I don't get confused," Haley responded.

Maybe not, but the outside world could be forgiven for being a little bewildered, at least. What has become apparent: Nobody in the White House reliably speaks on Trump's behalf — maybe not even Trump himself. The president is the biggest flip-flopper in American politics today.

It's happened on DACA. Syria. Health care. The list goes on. A Trump policy pronouncement is like Kansas weather: If you don't like it, wait 15 minutes. The flip is almost surely coming.

Which is why it's useful to remember why "flip-flopper" became a pejorative in the first place: It suggested a certain spinelessness, endless malleability, an uninspiring lack of core convictions. We've always known that the only thing Trump is really for is Trump himself; everything else is negotiable.

Trump's flexibility could, in some cases, be spun as a positive. "When the facts change, I change my mind," goes the famous quote. The problem? In precious few instances of Trump's flip-flops do we have evidence that the facts of a debate have changed. What has? Being the last person to speak to Trump on a topic.

This stuff matters. The future of the Dreamers depends on Trump's DACA policy. The future of farmers and workers depend on his trade policy. The future of anyone relying on insurance depends on his health-care ideas. To meander from position to position without signaling any real understanding of the consequences is to be cavalier with the very lives of millions of people, both inside the U.S. and beyond our borders.

Trump has cultivated an image as a straight shooter, but that's mostly because he eschews notions of politeness and decency as "politically correct." As with so many of Trump's transgressions, there's little reason to believe he'll pay a political price the way, say, John Kerry did. But that doesn't mean Trump's fickleness is good, or even benign, for the country he leads.

We look for leadership. We get endless flip-flops instead.