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Good morning, We start the final day of 2018 with the continuing government shutdown, Senator Elizabeth Warren’s preparations for 2020, and an investigation into the C.I.A.’s shadow war in Afghanistan.

Both sides dig in on budget impasse

With the partial government shutdown now in its second week, President Trump has reassured allies that he won’t yield on his request for $5 billion in funding for a border wall. But negotiations with Democratic leaders are at a standstill, and each side says the ball is in the other’s court.

What’s next: Democrats are preparing to pass a bill to fund the government as soon as they take control of the House on Thursday. However, uncertainty over what Mr. Trump might sign threatens to extend the shutdown, which affects 800,000 federal workers and has shuttered parts of nine cabinet-level departments.

Another angle: The concrete wall that Mr. Trump has repeatedly called for isn’t actually a wall and hasn’t been viewed as such since “early on in the administration,” the departing White House chief of staff, John Kelly, said in an interview. Mr. Kelly’s last day on the job is today.