VISITORS planning a trip to Washington DC are generally advised to avoid August, when it is too hot and humid to walk from museum to monument. Best to follow the lead of legislators and other savvy locals and steer clear of the place.

Congress of old knew what it was doing when it came up with the idea of August Recess. As one guide to the US Senate says, it is a chance for legislators to “spend time with family, meet with constituents in their home states, and catch up on summer reading”.

Nowhere does it recommend August as a good month to fly into one of the world’s most sensitive geopolitical hotspots and risk starting a third world war.

That, to her more alarmed critics, is what US Speaker Nancy Pelosi is doing with her “surprise” visit to Taiwan. Even some of her supporters have been left wondering why she has chosen to go there now and what she hopes to achieve.

It was in every way a historic occasion, the kind of jaw-dropping, heavy on the symbolism move that would have been at home in the Reagan or Kennedy eras.

The country has not had a visit from a politician of Ms Pelosi’s seniority for a quarter of a century, so of course the Taiwanese government was going to make the most of it.

When Ms Pelosi arrived at Songshan airport on Tuesday night she was surrounded by a sea of grey suits. If it had not been for her bright pink outfit you might have had trouble spotting her at all. Then again, Speaker Pelosi never usually has trouble making her presence felt. She cuts a tiny figure, but as third in line to the presidency she wields great power and influence. Where she goes, what she says, matters.

No-one could accuse Ms Pelosi of coming late to China. From her earliest days in Congress she has taken every chance to speak out against China and its abuse of human rights. Indeed, in 1991 she was part of a group of US politicians who went to Tiananmen Square to mark the 1989 massacre of pro-democracy activists.

Though China could hardly have been surprised at another wave of criticism from Ms Pelosi, it would have taken quite the leap of imagination to see her delivering it in person in Taiwan. We know from her clashes with Donald Trump and others down the years that she is hardly lacking in confidence, but this was something else.

China is predictably furious. “Those who play with fire will perish by it,” warned a government spokesman. More alarmingly, Beijing announced it would from today be stepping up its already heavy presence in the air and sea around Taiwan, and carrying out live fire exercises.

Ms Pelosi carried on with her schedule undaunted. This included receiving an award, the wonderfully-titled Order of Propitious Clouds with Special Grand Cordon, from Taiwan’s President Tsai Ing-wen. Accepting the honour, Ms Pelosi said the world faced a choice between democracy and autocracy. “America’s determination to preserve democracy here in Taiwan and around the world remains ironclad,” she assured her audience.

It is the kind of crisp, clear language that keeps diplomats awake at night. This is not the way US-China relations over Taiwan are supposed to be conducted. The policy is meant to be one of strategic ambiguity, as part of which America pledges, in law, to “stand with” Taiwan should China invade, but avoids going into detail on how it would do so.

It is a classic diplomatic fudge, designed to keep the peace in an otherwise impossible situation. Rather like the cloud, no-one really knows how it works, but it works.

So why go poking around now? Why, in Ms Pelosi’s words, decide that now is the time to “make unequivocally clear” that America will not abandon Taiwan? What has changed?

A cynic might wonder if the looming midterm elections in the US have had any influence on Speaker Pelosi’s travel plans.

But that does not fit with her long and honourable history of criticising China. Nor is she given to sabre rattling: see her opposition to the invasion of Iraq.

What has made the difference is Putin’s invasion of Ukraine. President Biden, who was reportedly not in favour of the Pelosi visit, has likened Taiwan to Ukraine, seeing the latter as a test. If Russia is not seen to pay a high price for its invasion of Ukraine, what is to stop China doing the same with Taiwan?

Earlier this year, while on his own tour of Asia, the President said he did not expect a Chinese invasion of Taiwan to happen, but if it did, America would defend Taiwan militarily. Viewed from that angle, Ms Pelosi is only repeating the policy as set out by her President, albeit in a more direct manner.

But the questions remain: why now and to what end? Ms Pelosi is not alone in thinking the policy of strategic ambiguity has had its day.

Like the rest of the world she has watched as China has grown richer and vastly more powerful. While the west was embroiled in Afghanistan and Iraq, China was everywhere else, quietly making friends and influencing people through its investments and loans.

Within the next decade, China could overtake the US as the world’s largest economy. The old order will be upended with an autocracy in the top spot. That’s a potential game-changer if ever there was one.

Throughout her career, Ms Pelosi has prided herself on her ability to get things done. She is the ultimate politician as pragmatist. With the west surprising everyone, not least itself, by uniting in support of Ukraine, she might see this as the ideal time to reset relations with China. Remind the world in general what America stands for.

While it is an admirable aim, it is probably 10-15 years too late. What is happening in Ukraine, dreadful as it is, would pale in comparison to the fallout from conflict over Taiwan.

In a world that is battered by Covid, wrestling with a climate emergency, and on the verge of recession, there is a lot still to be said for carrying on with strategic ambiguity for a while yet. Even more so given there is, as yet, no agreed upon replacement.

Ms Pelosi continues her August travels with stops in South Korea and Japan before heading home to the US. She has made her point on Taiwan; for now that is enough.