I went and read the article you cite.  Guess what?  It is so full of misconceptions that I suggest your author Thompson's opinion is worthless.  
Who says Ahmed Khadr was <i>"strongly linked to al Qaeda since the 1990s"</i>?  Khadr set up a charity, one that Revenue Canada allowed to issue receipts that qualified for a tax deduction.  If the USA had ever had a lick of proof of an operational link to al Qaeda surely his right to issue tax deductions would have been removed?
Your author Thompson makes the wild claim that eldest son Abdullah was <i>"was a
member of al Qaeda when arrested in 2004"</i>  Oh yeah?  I went to observe the extradition hearings, in late December 2005, when the US allegations were read out.  They said nothing about him being an al Qaeda member, your author Thompson just made that up.
Thompson claims Abdurahman was conscripted by the Taliban.  Also wildly incorrect. I've run out of room.  Give your author Thompson zero credibility...