True, they didn't do so when he was 14 and his consuming passion wascollecting hip-hop CDs with especially nasty lyrics.
And true, they didn't interfere when once he announced at 16 that he was going to drop out of Tamiscal High School - the elite "alternative" school where students determined their own course of study and only saw a teacher once a week.
And granted, they didn't put their foot down when he decided to become a Muslim after reading "The Autobiography of Malcolm X" and took to wearing long white robes and an oversized skullcap. On the contrary: His father was "proud of John for pursuing an alternative course" and his mother told friends that it was "good for a child to find a passion."
Nor did they object when he began spending more and more time at a local mosque and set about trying to memorize the Koran. Nor when he asked his parents to pay his way to Yemen so he could learn to speak "pure" Arabic.
Nor when he headed to Pakistan to join a madrassa in a region known to be a stronghold of Islamist extremists.
And his parents didn't balk when he went to fight in Afghanistan -but that, at least, they didn't know about: He hadn't told them. Perhaps he had learned to take their consent for granted.
Only once, it seems, did Frank Lindh and Marilyn Walker actually deny their son something he wanted. When he first adopted Islam and took the name Suleyman, they refused to use it and insisted on calling him John. After all, he had been named for one of the giants of our time: John Lennon.
Their refusal must have amazed him. For as long as he could remember, his oh-so-progressive parents had answered "yes" to his every whim, indulged his every fancy, permitted - even praised - his every passion.
The only thing they insisted on was that nothing be insisted on.
Nothing in his life was important enough for them to make an issue of: not his schooling, not his religion, not his appearance, not even whether he stayed in America or moved - while still a minor -to a benighted Third World oligarchy halfway around the world.
Nothing. Except, of course, their right to call him by the name of their favorite Beatle.
Devout practitioners of the self-obsessed nonjudgmentalism for which the Bay Area is renowned, Lindh and Walker appear never to have rebuked their son or criticized his choices. In their world, there were no absolutes, no fixed truths, no mandatory behavior, no thou-shalt-nots.
If they had one conviction, it was that all convictions are worthy - that nothing is intolerable except intolerance.
But even in Marin County, there are times when children need to hear "no" and "don't." They need to know that there are limits they must respect and expectations they must try to live up to. If they cannot find those limits at home, they are apt to look for them elsewhere. Newsweek called it "truly perplexing" that John Lindh, who "grew up in possibly the most liberal, tolerant place in America ... was drawn to the most illiberal, intolerant sect in Islam."
There is nothing perplexing about it. He craved standards and discipline. Mom and Dad didn't offer any. The Taliban did.
Even when it was clear that their son was sinking into Islamist fanaticism, they wouldn't pull back on the reins. When Osama bin Laden's terrorists bombed the USS Cole and killed 17 American servicemen, John Lindh e-mailed his father that the attack had been justified, since by docking the ship in Yemen, the United States had committed "an act of war." Frank Lindh now says that the message "raised my concerns" - but that didn't stop him from wiring his son another $1,200. After all, says Dad, "my days of molding him were over."
It isn't clear that they ever began.
It came as a jolt to his parents when John Lindh turned up at the fortress near Mazar-e-Sharif, sporting an AK-47 and calling himself Abdul Hamid. But the revelation that their son had enlisted in Al Qaeda and supported the Sept. 11 attacks brought no words of reproach to their lips.
John Lindh deserved "a little kick in the butt" for keeping them in the dark about his plans, his father said, but otherwise they just wanted to "give him a big hug." His mother, meanwhile, was quite sure that "if he got involved with the Taliban he must have been brainwashed.... When you're young and impressionable, it's easy to be led by charismatic people."
Yes, it is, and it's a pity that that didn't occur to her sooner.
If she and Frank Lindh had been less concerned with flaunting their open-mindedness and more concerned with eveloping their son's moral judgment, he wouldn't be where he is today.
His road to treason and jihad didn't begin in Afghanistan. It began in Marin County, with parents who never aid "no."