Barro largely blames Republican epistemic closure on the party’s think tanks:
Conservative think tanks haven’t developed plausible alternative ideas on health policy because that isn’t what donors want them to do. For the last four years, the project has been finding anything to tear down Obamacare, not to find a replacement. … When people talk about the conservative echo chamber, they often focus on lowbrow outlets like Fox News, talk radio and Breitbart.com. Certainly these are often embarrassing and counterproductive for conservatism, most recently with the “Friends of Hamas” fiasco. But every movement contains stupid people reading stupid things. The special reason conservatives can’t think straight is that their supposedly smart institutions are inside the echo chamber, too.