The only escape route from this horror, said the friend next to me on the sofa at noon today, is if this final set goes to 40,000-40,000. That way, we won’t have to return to the real world until after the next US election.

In the event, this fantastical piece of sporting nostalgia ended in Roger Federer’s favour within minutes. But for the preceding three and a half hours, you could almost persuade yourself that you’d slipped through a tear in space-time, and gone back eight years to the last time the Fed and Rafael Nadal duked it out over five sets for the Australian Open title.

The date of that one, won by Rafa, feels viciously poignant today. On 1 February, 2009, Barack Obama had been in the White House for under a fortnight, and the echo of his sublimely humane inauguration address had the world light-headed with hope.

Not even a fortnight after Donald Trump mistook his inauguration speech for a Mussolini tribute act, it would take the Hubble telescope on steroids to detect a slither of optimism. The banning of residents and passport holders from, not to mention people merely born in, almost every Muslim nation with which Trump has no business relationship creates a heavier, more broodingly dark atmosphere than anyone too young to remember the Cuban Missile Crisis will recall.

The controversial orders Donald Trump has already issued Show all 9 1 /9 The controversial orders Donald Trump has already issued The controversial orders Donald Trump has already issued Trump and the media White House Press Secretary Sean Spicer takes questions during the daily press briefing Getty Images The controversial orders Donald Trump has already issued Trump and the Trans-Pacific Partnership Union leaders applaud US President Donald Trump for signing an executive order withdrawing the US from the Trans-Pacific Partnership negotiations during a meeting in the Roosevelt Room of the White House in Washington DC. Mr Trump issued a presidential memorandum in January announcing that the US would withdraw from the trade deal Getty The controversial orders Donald Trump has already issued Trump and the Mexico wall A US Border Patrol vehicle sits waiting for illegal immigrants at a fence opening near the US-Mexico border near McAllen, Texas. The number of incoming immigrants has surged ahead of the upcoming Presidential inauguration of Donald Trump, who has pledged to build a wall along the US-Mexico border. A signature campaign promise, Mr Trump outlined his intention to build a border wall on the US-Mexico border days after taking office Getty Images The controversial orders Donald Trump has already issued Trump and abortion US President Donald Trump signs an executive order as Chief of Staff Reince Priebus looks on in the Oval Office of the White House. Mr Trump reinstated a ban on American financial aide being granted to non-governmental organizations that provide abortion counseling, provide abortion referrals, or advocate for abortion access outside of the United States Getty Images The controversial orders Donald Trump has already issued Trump and the Dakota Access pipeline Opponents of the Keystone XL and Dakota Access pipelines hold a rally as they protest US President Donald Trump's executive orders advancing their construction, at Columbus Circle in New York. US President Donald Trump signed executive orders reviving the construction of two controversial oil pipelines, but said the projects would be subject to renegotiation Getty Images The controversial orders Donald Trump has already issued Trump and 'Obamacare' Nancy Pelosi who is the minority leader of the House of Representatives speaks beside House Democrats at an event to protect the Affordable Care Act in Los Angeles, California. US President Donald Trump's effort to make good on his campaign promise to repeal and replace the healthcare law failed when Republicans failed to get enough votes. Mr Trump has promised to revisit the matter Getty Images The controversial orders Donald Trump has already issued Donald Trump and 'sanctuary cities' US President Donald Trump signed an executive order in January threatening to pull funding for so-called "sanctuary cities" if they do not comply with federal immigration law AP The controversial orders Donald Trump has already issued Trump and the travel ban US President Donald Trump has attempted twice to restrict travel into the United States from several predominantly Muslim countries. The first attempt, in February, was met with swift opposition from protesters who flocked to airports around the country. That travel ban was later blocked by the Ninth Circuit Court of Appeals. The second ban was blocked by a federal judge a day before it was scheduled to be implemented in mid-March SANDY HUFFAKER/AFP/Getty Images The controversial orders Donald Trump has already issued Trump and climate change US President Donald Trump sought to dismantle several of his predecessor's actions on climate change in March. His order instructed the Environmental Protection Agency to reevaluate the Clean Power Plan, which would cap power plant emissions Shannon Stapleton/Reuters

The stories of heartrending exclusions already stack up. You may have heard of Iraqi interpreters who for a decade worked in great danger for the US military, but whose long-awaited and heavily vetted visas were revoked on Saturday; of green card holders with a clear legal right to US residency denied re-entry after visiting sick relatives; of the Iranian director who can’t attend the Oscars at which his film will be a nominee.

You won’t be aware of a friend’s father who missed the Roger-Rafa classic because he was flying to the States. A British national with no other passport, he was once such a heroic critic of the Ayatollahs that, after he fled Tehran, they sent death squads to London to assassinate him.

When he arrived at Heathrow this morning, he had no idea whether, by dint of being born in Iran, he would be detained and sent home on suspicion of being a puppet of the regime which so assiduously tried to kill him.

So anyone unsure whether the mantle of office would diminish Trump’s megalomaniacal brutishness has their answer. He told us what he would do, and lo, verily, it hath come to pass – albeit the reality is worse than feared. Who thought that a Muslim ban widely dismissed as no more than campaign histrionics would extend to green card holders? But Trump is the greatest limbo dancer in political history: however low he sets the expectations bar for himself, he finds the way to squeeze beneath it.

Evidently he is racing towards destructive war with those parts of the media that see no distinction between a whopper and an alternative fact, and also with the judiciary. The ban’s rejection by a federal judge, Ann Donnelly, can only be the prelude to a Supreme Court case. If the Supremes declare it unconstitutional, would that restrain his dictatorial instincts or inflame them? Would civil unrest on a scale unseen since the 1960s race riots temper his lunacy or exaggerate it? Is he capable of pragmatism, in other words, or does the seam of messianic self-regard run too deep to be penetrated by external pressures?

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While we shiver in wait for the answer, innocent lives are being destroyed by what the Somali-born Mo Farah called ignorance and prejudice. It does more than rend the heart. It fills it with an ominous bleakness the like of which few have experienced.

Although the pervasive gloom leaves little room for other emotions, I can’t deny a pang of sympathy for Theresa May. Fair enough if you decline to share it after her wretched efforts to be silent about the Muslim ban. But try to imagine the agony, for a fundamentally moral human being, to find herself squeezed between the rock of Trump’s wickedness and the hard place of needing his indulgence on the trade deal front.

One minute she’s holding his weeny hand, and then she’s ingratiating herself with Turkey’s tyrannical President Erdogan – the next she’ll be kneeling before the Chinese. At this rate, she’ll be zigzagging between the nastier central Asian republics and Robert Mugabe before Roger and Rafa make their Centre Court returns in late June.

May is neither callous nor stupid. She knows that for evil to triumph, all that’s required is for good women to do nothing. She also knows how desperately economic growth will depend, post-Brexit, on trade relations with regimes that show a nauseating disregard for human rights. The tension between these competing bits of knowledge might be powerful enough to break a sensitive soul in two.