Story highlights Although Bush was not aggressively critical of Trump, he showed no signs that he was warming up to him

Trump, he said, has "been phenomenally good at using the new way of communicating" to gain free media coverage

Washington (CNN) Jeb Bush on Saturday said Donald Trump is a skilled politician with a "very powerful message" about shaking up Washington, but he argued the presumptive Republican nominee is campaigning in a way that's "preying on people's angst rather than offering tangible solutions."

At a three-hour event in Amsterdam hosted by the Nexus Institute, the former Florida governor and GOP White House hopeful delivered a speech and took part in a panel discussion about the changing dynamics of American democracy. The discussion, in part, explored trends that have paved a path for the rise of candidates such as Trump and Vermont Sen. Bernie Sanders, who is running as a Democrat.

Although Bush was not aggressively critical of Trump, as he had been during his campaign, he showed no signs that he was warming up to the presumptive Republican nominee, like some other establishment Republicans have started doing.

Still, Bush said, he doesn't blame voters who are supporting Trump.

"What I fear is that people, kind of looking down their nose, will say the people that are supporting Donald Trump are a bunch of idiots. They're not. They're legitimately scared. They're fearful. They're not as optimistic for legitimate reasons and there should be respect for that," he said. "And on the other side, a similar respect needs to be shown."

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