Last week, Singapore’s post-independence hero, Lee Kuan Yew, marked his 90th birthday.

He has led an amazing life, and though a ruthless old curmudgeon, he has always been among the most rewarding interview subjects.

After our first joust in 1991, I attended Singapore’s National Day reception and saw him standing alone in a corner ringed by security men.

Taking a deep breath, I strolled over and thanked him for the interview. It had been a good one and Asiaweek had run it as the cover story.

Lee’s eyes narrowed and he gave me a long glacial gaze. To break the silence, I blurted out that I hoped he’d been happy with the story.

He pounced. “Oh? Is that important? Does it matter whether I am happy or unhappy with it?”

If only words would have come, earthy expletives preferably; but I was flummoxed, my mind swirling.

“Remind me, what interview was this?” he said.

His wife, a proverbial dragon lady, whom he described as “an intellectual equal” and “soulmate”, thankfully moved forward at that moment and I introduced myself to her.

She said: “You are in a difficult position as a journalist in Singapore, Mr Mitton. If you tell the truth you will get into trouble from my husband, if you don’t tell the truth you will get sacked by your editor.”

Lee cracked a sliver of a smile as if the oracle had spoken, then they turned away, dismissing me like a speck of dust brushed off a sleeve.

The dismissal turned out to be not only from their presence that evening, but from Singapore itself; for soon afterwards, the authorities refused to renew my visa, forcing me to leave the country.

Still, other interviews were later granted, and in a final long and fruitful session that revolved around the publication of his memoirs, Lee kindly signed a copy of his book for me.

On the title page, he wrote: “To Roger Mitton, with my best answers to your spiky questions. Lee Kuan Yew.” Ya gotta like the guy.

His dragon lady died three years ago and now he is 90 and knocking on heaven’s door. Let’s hope he goes quickly and painlessly, though that is not the way he treated his opponents.

They were many and all were cruelly dispatched: his rival People’s Action Party leader Ong Eng Guan, his country’s former president Devan Nair, its former solicitor general Francis Seow, and myriad pesky journalists.

None, however, suffered more brutal and malicious torture than the opposition Workers’ Party leader, Joshua Benjamin Jeyaretnam.

Lee loathed him because JBJ was fearless and refused to be cowed by the PM’s thuggery, and because he broke the stranglehold of Lee’s PAP and won the 1981 Anson by-election.

That result was a thunderbolt; it marked the first time since independence that one of Lee’s men had lost an election.

Once in parliament, where it was him against 74 government MPs, Jeyaretnam gave them hell. Lee and his front bench could not take it.

Grounds were found to charge JBJ with misreporting party accounts. He was convicted, jailed, deprived of his seat and disbarred from practising law.

Undaunted, he appealed to the Privy Council in England, as he was then entitled to do, and his conviction was quashed.

The Law Lords ruled that he and a party colleague had “suffered a grievous injustice. They have been fined, imprisoned and publicly disgraced for offences of which they are not guilty”.

The ruling did not faze Lee. He quickly abolished the right of appeal to the Privy Council and JBJ was gone.

Soon afterwards, so was I. But not before taking Jeyaretnam to lunch at that bastion of the establishment, the Singapore Cricket Club.

Boy, did that feel good. And anyway, I’d done three years as a foreign correspondent in Singapore; it was long enough.

JBJ died in 2008. And Time’s winged chariot is hurrying upon Lee. But for now: Happy Birthday, you vicious old coot. I mean it.