In a word, yes, assuming they had lots of help from the CIA to deliver their persuasion.
I would not have said this was possible five years ago. But in 2017, cognitive scientists know how to reprogram a human brain fairly effectively. They have weaponized what hypnotists have been doing for decades.
As luck would have it (sort of) we can test persuasion ideas at Guantanamo Bay without any cruelty whatsoever. There would be no hardcore “brainwashing,” just a series of pleasant experiences engineered to get a certain outcome.
I don't know enough to say if Adams is right or wrong. So far it doesn't work.
Although to be fair, "hookers and blow" is better than "beheading and blowing things up."
But even if he is 100% right, how many Moslem jihadis are in Guantanamo Bay to be reprogrammed in controlled circumstances and how many of them and the potential recruits for the jihad are out in the world being persuaded every day that being a jihadi is just swell?
So maybe jihadis can be reprogrammed. But how do we make it stick when they are back in their environment being reprogrammed back? After all, that environment right now is having no problem getting the jihadi outcome. Could we risk releasing them?
But wouldn't it just be cruel to "fix" the inmates and then keep them imprisoned because they'd just be reprogrammed to jihadi mode again if freed?
Until we figure out a solution to that problem--which involves Islamists being beaten in the Islamic civil war so the wider environment doesn't program jihadis--lead persuasion is the only answer, I think.