With large sections of the federal government shut down, thousands of public employees are bracing to work without pay until Congress and President Trump agree how to spend taxpayers’ money and reconcile ideological differences.

Mr. Trump said he’s prepared for a “very long” shutdown over his demand that a spending bill include $5 billion to build a wall along the border with Mexico.

“It’s very possible that this shutdown will go beyond the 28th and into the new Congress,” Mick Mulvaney, the director of the Office of Management and Budget, said on “Fox News Sunday.”

It’s hardly the first time Congress and the president have faced a budget impasse: There have been at least 21 times in the last four decades that the government hasn’t been able to pass some form of a spending bill on time, according to the Congressional Research Service and news reports.