Jack Welch, the former chief executive of General Electric, thinks Donald Trump is not being ruthless enough with the bureaucracy in Washington, D.C.

“I think he was an entrepreneur who ran his own shop and he never ran a bureaucracy,” Welch said on CNBC’s Squawk Box. “It was a family business, which he ran beautifully. He was successful. But you can’t keep doing that.”

Welch advised the president to get more aggressive with the Deep State government bureaucrats whose leaks have triggered much of the chaos now engulfing the White House.

“If you run a bureaucracy, they’re in the weeds, they’re behind the desk, they’re whispering around the water-cooler. You’ve got to nail them and get them the hell out of there,” Welch said.

Welch said he’s a supporter of the president’s agenda but a critic of his management skills. The handling of James Comey, Welch said, was a rookie mistake. Given Trump’s earlier praise of the former FBI director, calling Comey incompetent was a mistake. Instead, the president should have praised Comey even as he fired him,

“I think without question we have a guy that on the right agenda with crappy management practices,” Welch said.

If he had to give a grade to Trump’s management skills, Welsch said he’d give Trump a “D minus.”

“And I’m an easy grader,” Welch said.

Welch said he would Trump straight As on boosting morale of business owners, on picking members of his cabinet and on his Supreme Court pick.

Welch also warned that an impeachment of President Donald Trump would trigger a huge market sell-off.

“An impeachment proceeding would blow the market away,” Welch said.