Airport security screeners could quit en masse, grounding flights. The federal courts could stop hearing civil cases. City buses could stop running.
And 38 million Americans could stop getting food stamps.
Officials from Washington to Wall Street are pondering nightmare scenarios if the partial U.S. government shutdown that is already the longest on record extends into spring -- or beyond.
“Shutdowns don’t get bad linearly; they get bad exponentially,” said Sam Berger, a senior adviser at the Center for American Progress, who worked at the Office of Management and Budget under President Barack Obama.
President Donald Trump’s administration has found creative means to blunt some of the shutdown’s effects -- figuring out ways to process tax refunds, for example. Yet agencies that have been able to dip into user fees, leftover funds and other revenue streams are running out of those reserves.
Lawsuits are already testing the administration’s ability to keep on the job unpaid workers, hundreds of thousands of whom missed their first paycheck last week.
Efforts by Republicans such as Senator Lindsey Graham of South Carolina to cut an immigration deal to resolve the impasse have failed, and Trump on Monday rejected his latest proposal. An administration official said the White House is game-planning for the shutdown to continue through at least the end of February.
Beyond its direct effects on businesses, economists say the shutdown threatens to shake consumer confidence and chip away at retail sales, particularly as unpaid federal workers and contractors forgo spending on cars, new homes and even entertainment.
To be sure, three-quarters of the government was funded by appropriations enacted before the standoff began. Departments such as Defense, Labor and Health and Human Services remain in business. Still others, like the U.S. Postal Service and U.S. Federal Reserve, have funding streams separate from what Congress provides.
But the shuttering of more than a dozen departments and agencies -- from Homeland Security to the Environmental Protection Agency -- is being felt across the country, threatening the economy, public safety, businesses and people’s wallets.