WASHINGTON - "Yes," U.S. forces will defend Taiwan if it is invaded by China. Russian President Vladimir Putin is a "butcher" who "cannot remain in power." And the COVID-19 pandemic is "over."

U.S. President Joe Biden's tendency to ad-lib in impromptu press situations is often referred to in Washington as his "gaffe" problem.

While the term refers to a blunder, Biden's remarks often aren't quite that - they betray deeper truths about his thinking and occasionally offer the public a better window into the administration's approach than that offered by spokespeople, from press secretary Karine Jean-Pierre to members of his Cabinet.

As Biden himself told steelworkers this month: "No one has ever doubted I mean what I say; the problem is I sometimes say all that I mean."

Biden's casual and unscripted remarks can cause far-reaching diplomatic ripples, forcing White House staff to scurry to "walk back," to use another Washington term, his remarks, trying to smooth over upsets, without saying outright that he misspoke.

After Biden spoke on defending Taiwan in a CBS News "60 Minutes" interview this month, officials quickly said that U.S. policy towards Taiwan is unchanged.

But he has said similar things before as president. His apparent willingness to commit U.S. forces to a battle in Taiwan clears up a long-standing disconnect in U.S. policy towards Taiwan.

Presidents have said since the 1970s that they support a "One China" policy that declares Taiwan a part of China, but also that they are bound by a 1979 law to help Taiwan defend itself. Biden's response suggests the U.S supports One China in concept, but Taiwan's defense in practice.

'WALK BACK' ON PUTIN

His statement about Putin in Warsaw in March was quickly walked back by a White House official who said "the President's point was that Putin cannot be allowed to exercise power over his neighbors" and not a discussion of "regime change."

Whatever the White House says, it is clear that the president's private view is that Putin is unfit for office, implying that he will use U.S. policy to weaken Putin whenever possible.

The White House has long said that it would be "driven by science" in determining when to end the COVID public health emergency. Biden made his "the pandemic is over" remark on the sidelines of September's Detroit auto show as hundreds of Americans continue to die of the disease daily.

But they reflect changes in the administration's approach to the disease. A new vaccine campaign is being compared by U.S. officials to annual flu shot drives, and the Centers for Disease Control and Prevention relaxed its guidance that masks always be worn in healthcare settings after Biden spoke.

The loose-lipped quality is not new. As vice president during the Obama administration, Biden famously disclosed support for same-sex marriage before the president had been willing to do so.

"He's always had a reputation for saying what he was thinking," said former U.S. Senator Ted Kaufman, who has worked with Biden for a half century and remembers the onetime senator taking constituents' questions at a Wilmington, Delaware, train station.

MANAGING BIDEN'S CANDOR

The candor is the bane of anxious young press aides who let out long sighs or expletives when the president approaches reporters to answer questions in ad hoc briefings - which he enjoys doing but has suggested gets him in trouble with his staff.

Senior aides, worried about having to explain an indelicate, imprecise or speculative remark, rarely make Biden available for long-form interviews. The "60 Minutes" interview, which included both the troop commitment in Taiwan and the pandemic comment, was Biden's first since a brief exchange in July with an Israeli television anchor.

"Generally, staff are risk-averse, and they figure in news conferences or high-profile events, if you make a mistake, it takes some while to clean up," said Towson University political science professor emerita Martha Joynt Kumar.

Biden has had far fewer formal interviews than his recent predecessors, Kumar's research shows.

Biden has held 17 press conferences, 39 interviews and engaged in 300 hundred informal back-and-forth exchanges with reporters in his presidency, according to Kumar's data through July. That compares with an average of 41 press conferences, 112 interviews and 172 informal exchanges for the six preceding presidents over the same time frame.

While Biden's off-the-cuff remarks sometimes reveal deeper truths about his policy or opinions, other times they are simply misleading.

Biden, 79, said at a July event that he has cancer. An aide later said on Twitter that Biden had non-melanoma skin cancers removed before he took office in January 2021 and that "this is what the President was referring to."

(Reporting by Trevor Hunnicutt; Editing by Heather Timmons and Grant McCool)