The shutdown today: Trump says he'll 'never, ever back down'

What's up with the partial government shutdown on Day 25:

WHAT'S NEW

With the US government mired in shutdown week four, President Donald Trump is rejecting a short-term legislative fix and digging in for a fight, declaring he will "never, ever back down".

Air travellers endured waits of more than an hour to get through domestic checkpoints at the world's busiest airport in Atlanta on Monday. No-shows among screeners across the nation soared Sunday and again Monday, when the Transportation Security Administration (TSA) reported a national absence rate of 7.6 per cent, compared with 3.2 per cent on the comparable Monday a year ago.

Like some of his recent predecessors, Trump is carefully picking and choosing where he'll travel during the partial government shutdown.

QUOTE OF THE DAY

"It's chaos out here," passenger Vincent Smith said Monday as he stood in a line that snaked through the Atlanta airport's atrium and baggage claim areas. "This line, I've been here about 15 minutes, and it has moved 2 feet."

WHAT'S COMING NEXT?

Trump is expected to sign legislation this week authorising back pay for some 800,000 federal workers who either have been idled or are working without pay for as long as the shutdown lasts.

WHAT REMAINS CLOSED?

Nine of the 15 Cabinet-level departments have not been funded, including agriculture, homeland security, state, transportation, interior and justice. Some iconic National Park facilities are shuttered, as are the Smithsonian museums and the National Zoo in Washington. Nearly everyone at NASA is being told to stay home, as are most at the Internal Revenue Service, which processes tax returns and issues refunds, though the administration says it will issue refunds during the shutdown.

WHO IS AT WORK BUT NOT GETTING PAID?

Some 420,000 federal employees whose work is declared essential are working without pay, including at the FBI, TSA, and other federal law-enforcement offices. Some staff at the State and Homeland Security departments are also working without compensation.