Cognitive Style. Greenstein described this as the style “with which the president processes the Niagara of advice and information that comes his way.” Trump often appears to adopt the advice of the last person he’s talked to. Other times, he’s adamant about sticking to a policy he’s been advised to abandon. His sympathy for Vladimir Putin and his insistence on pulling out of the Paris Agreement on climate change come to mind in this regard.
Trump’s substitute for books is TV news. It’s a source of advice and leads to job offers. Trump has no wise man to rely on. Nixon had Kissinger. Reagan had Jim Baker and Ed Meese. Bush the Younger had Cheney.