Leading left-leaning economists, economics journalists and other so-called experts are skeptical over President Trump’s budget proposal, which ambitiously seeks to reach an economic annual growth rate of three percent by 2021.

Harvard Professor and former Treasury Secretary Larry Summers suggested that Trump’s budget proposal is preposterous.

Apparently, the budget forecasts that U.S. economic growth will rise to 3.0 percent because of the administration’s policies — largely its tax cuts and perhaps also its regulatory policies. Fair enough if you believe in tooth fairies and ludicrous supply-side economics.

Summers also wrote that the budget would justify “failing a student in an introductory economics course.”

Former Office of Management and Budget Director Jim Nussle told CNBC on Tuesday that Trump’s budget is unlikely to reach its intended goal of annual three percent growth.

“When you say we’re going to get to 3 percent growth and then you paint a picture of how you’re going to get to 3 percent growth, most economists say that’s unrealistic given the current trend line,” Nussle said.

Jordan Weissmann, Slate’s senior business and economics correspondent, argued that Trump’s budget is “frightening.”

“He’s granting Paul Ryan permission to cut away. And that, ultimately, is what makes Trump’s budget so frightening. Even if the whole package probably isn’t going to become a reality, it’s still a sign that he won’t stop Republicans enacting whatever rash part of their agenda they manage to legislate,” Weissmann wrote.

Former Vice Chair of the Federal Reserve Alice Rivlin argued that Trump’s budget is “optimistic.”

“They are very optimistic,” she said. “We haven’t seen 3 percent growth for a long time.”

Senator Joe Manchin called Trump’s budget “alarming.” “It’s just very demoralizing to see this type of budget being out,” he said. “Every state is going to be affected, there’s not one state that’s going to be spared on this.”

Binyamin Appelbaum, who covers economic policy for The New York Times also condemned Trump’s budget, claiming that while it adds growth, it does not take in consideration the added costs.

“When the government cuts taxes, it collects less money. That is the purpose of a tax cut. But Mr. Trump’s budget does not include any hint of a decrease in federal revenue. To the contrary, it projects that federal tax revenue will increase every year for the next decade,” Appelbaum wrote.

As Breitbart News pointed out Tuesday, a lot of these people were a lot less skeptical when the Obama administration’s budget projected growth rates as high as 4.6 percent. They should have been–GDP growth never got close to that in Obama’s eight years.

Here are some other reactions:

It appears that Trump budget involves two scoops of voodoo economics: faster growth *and* tax cuts without a fall in revenue as % of GDP — Paul Krugman (@paulkrugman) May 23, 2017

Not getting as much attention as it should: The Trump budget proposes huge cuts in global health, from AIDS to malaria to TB. Sad. — Nicholas Kristof (@NickKristof) May 23, 2017

Trump’s budget is a right-wing rallying cry that will hurt the poor, disabled and elderly https://t.co/R1OlnJrIg6 pic.twitter.com/pwxtFUlnYr — NYT Opinion (@nytopinion) May 23, 2017

Watch Elizabeth Warren rip apart President Trump's education budget. pic.twitter.com/1AZ04viCsR — AJ+ (@ajplus) May 24, 2017

Tom Ciccotta is a libertarian who writes about economics and higher education for Breitbart News. You can follow him on Twitter @tciccotta or email him at tciccotta@breitbart.com