How will the shutdown end? Job action, sick in, strike, walk-out by enough of the federal workforce to slow functions of their department or agency, and create a crisis for the airlines, the federal prisons, the IRS, the federal courts, food safety inspections, NASA, CDC..?..you name it. Your guess is as good as mine. Trump doesn't know or care about what the 800,000 federal workers do. He doesn't care about them or their families. He doesn't care about the services they provide, who they provide them to, or the lives and businesses of those in the private sector who have contract work with the federal government.  It appears it will take a major crisis in air travel... law enforcement,... tax collection... IRS functions...border patrol/ICE..FAA... for Trump, McConnell and most important,  the Republican base, to bring this to an end.  None of these GOP folks give a damn until the sheet hits the fan and empties their wallets, affects their job or lifestyle, or threatens their political career.

One thing we know about Republicans in government: they go merrily along serving the rich, until a crisis develops, usually due to their own irresponsible actions, at which point they begin to recognize there is a big problem, and they look to Democrats for help in getting through it.

No telling what will break the dike on this attempt at legislative extortion by Trump, but it is likely to be a siezing up and collapse of some part of the federal government. Caused by workers tired of being used as unpaid pawns.

The one thing President Trump has not talked about publicly during 13 days of the partial government shutdown is the 800,000 federal workers who are not being paid because of it. 

Mr. Trump’s apparent indifference to the Transportation Security Administration agents, correctional officers, scientists and other federal employees caught in the cross hairs of a political standoff presents a remarkable contrast with how other presidents have made a point of trying to demonstrate their empathy during other shutdowns. In 2013, for instance, President Barack Obama wrote an open letter to the workers affected when the government was closed.

“None of this is fair to you,” he wrote, adding, “You and your families remain at the front of my mind.”

link

From furloughs at the Justice Department to confusion in the courts, to prison officers working without a paycheck, the shutdown has challenged the nation’s courts and criminal justice system and those whose livelihoods depend on them, slowing some cases while throwing others into disarray.

Federal district courts are still operating because they have revenue from court fees and other sources aside from congressional appropriations. But those funds may run out as soon as next Friday,

link