It's started already.
The England players have barely unpacked their suitcases at their Portugal training camp and there is already a distinct change in mood.
The eternal optimists are making noise. The big "ifs" have begun.
What if Roy Hodgson plays all the youngsters... what if Steven Gerrard doesn't slip over his own laces... England could win the World Cup.
No, no, no, no, no. Don't do it to yourselves. It's just not worth it. Step back from the precipice. Move away from the ledge. See reason. See common sense. See highlights from England's performances at Euro 2012.
No, don't do that. You'll jump off the ledge.
But misplaced optimism is taking hold once again, as it does every four years, like a dramatic case of Tourette's syndrome. Instead of swearing, a sufferer suddenly blurts out: "England are going to win the World Cup!"
At which point, he dances around singing: "Eng-ger-land!... Eng-ger-land!... Eng-ger-land!"
And that's just no way for a principal to behave during school assembly.
This tournament is slightly different, however, because it's no longer cool to champion England's chances after the humiliating drubbings back in 2010 and the non-football of Euro 2012.
Mocking the afflicted is trendy now. Publicly, we're all on message. We're all repeating the same mantras.
England will need a miracle to get out of the group... England will be lucky to get a point... Ryan Giggs has scored more times within his own family than Wayne Rooney has at the World Cup... That sort of thing.
But the "what ifs" can't help themselves.
They accept that championing England's cause is unfashionable, but the optimism is addictive, buried deep within the soul, impossible to shake off.
They end up sounding like the incurable bigot who says: "I'm not a xenophobe, but..."
Earlier this week, I heard a voice say: "I know England always disappoint, but what if Hodgson plays with the youngsters. There is a chance they could go all the way."
I couldn't listen to such blinkered nonsense any more. The voice was mine.
I punched myself in the face just to stop talking.
But it's all Hodgson's fault. He has complicated matters by giving England followers hope where there is usually frustration.
For the first time in forever - I'm quoting Frozen lyrics to win over younger readers - he has picked a youthful, vibrant, attacking, speedy squad of boy racers.
Where the hell did that come from?
This is a manager who has traditionally displayed all the artistic flair of a town-council painter.
Give Hodgson a tin of paint and he'd whitewash the Sistine Chapel.
Suddenly, he thinks he's the Michelangelo of international management. He's wearing a beret and dabbing at his water colours.
This is the last thing the "what if" gang needed. They seldom require further encouragement.
At least Hodgson kept it simple before, picking the rusty golden generation to waddle across the penalty box with their walking frames, leaning against a parked bus.
They soon made the optimism addicts go cold turkey.
There are only so many times John Terry or Joleon Lescott can fall over and Ashley Young can get arrested for impersonating a winger before even the most biased of disciples acknowledges that England are rubbish.
Had Hodgson coaxed Terry out of retirement and lumped the ball up to Big Andy Carroll as expected, then England's early exit would've temporarily cured the foolish addiction to hope. (By the way, it's now a pundit's law that Carroll's name must be prefixed by the adjectival "big", suggesting either an unhealthy obsession with his height or that someone has seen him naked in the dressing room).
Instead, Hodgson messed with our heads.
Now we're mumbling positive comments like: "I know England's role is to get routinely humiliated in the knockout stages, but what if he goes with Daniel Sturridge, Raheem Sterling, Ross Barkley or Adam Lallana... what if England follow Liverpool's system... No, I don't mean they choke and throw away silverware... the other system, the attacking 4-2-3-1 thing with youth and pace."
It's a slippery slope. Go down that road and, before you know it, you're leaning over to a friend and whispering: "What if England won a penalty shoot-out this time?"
That's the moment to seek medical attention. You're skirting the fringes of insanity.
So fight the temptation to be optimistic now. It's just too dangerous.
Hope and England go together like Rooney's head and human hair. Don't knit the two together.
This article was published on May 21 in The New Paper.
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