Is it too much to wonder whether continual and habitual assaults on the honesty, intentions, patriotism, and professionalism of scientists and intellectuals, a reflexive readiness to dispute the validity and usefulness of scientific and intellectual inquiry, in short the open adoption of anti-scientific and anti-intellectual attitudes and practices by some conservatives may also have played a role in such dramatic and long-standing trends?

Really? Tell me more about these "continual and habitual assaults"? Because all I've been seeing are continual and habitual assaults by intellectuals and experts, including scientists, on common sense, good faith and the social compact. If conservatives are making a case against the sins of intellectuals and scientists, it's because a whole lot of the latter are being revealed as lying, morally bereft opportunists willing to corrupt science (or economics, etc.) for epistemic vanity, personal aggandizement and the false idols of feel-good orthodoxy. (More widely, the masses are only now recognizing the decades-long damage produced on our society by people with advanced degrees from Harvard.) I would frame the problem not as an assault against science by backward conservatives but as the betrayal of society and the scientific method by scientists (indeed the betrayal of democracy by a papacy of experts), and the reasonable conservative (or libertarian, or classical liberal) counter-assault against arrogant and pious elitism. This is the most exhilarating and salutary social movement in my lifetime.

And there also seems to be in your essay an echo of the argument that fighting jihadists creates more jihadists. This has never been proven, and sidesteps the problem of jihadism (or junk science, in this case).

I grew up among the intellectual set. Now I'm about as avowed an anti-intellectual as you can find. Call this my own epistemic closure.