Sunday: Paul, Coons, Cheney

Widely viewed as a force for stability in an often turbulent administration, Defense Secretary James Mattis this week joined the ranks of secretaries set to depart President Trump's cabinet in the new year.

The president thanked "General Mattis" for his service late Thursday, trumpeting the "tremendous progress" made under a defense secretary he once speculated was "sort of a Democrat."

President Trump and Mattis often clashed, their differences coming to a head over President Trump's abrupt decision this week to pull out of Syria.

"We have defeated ISIS in Syria," the president had tweeted, "my only reason for being there during the Trump Presidency."

But the claim drew a sharp rebuke from lawmakers and American allies, pointing out recent assessments by his own State and Defense Departments contradicting him.

The pullout also prompted a personal appeal from Mattis, who on Thursday sought in vain to persuade the president to reverse course on it and an additional planned drawdown in Afghanistan.

"Because you have the right to have a Secretary of Defense whose views are better aligned with yours on these and other subjects," Mattis wrote Thursday in his resignation letter, "I believe it is right for me to step down from my position."

Also this week, thousands across President Trump's executive branch are bracing for a possible third government shutdown this year.

Paychecks for more than 800,000 federal employees could be stalled and offices throughout the bureaucracy shuttered. Markets plunged on news of an increasingly certain federal closure, thought unlikely days ago.

Hounded by conservative critics, the president insisted he would make good on his shutdown threat if Democrats did not support demands for five billion in "steel slats" money for the U.S.-Mexico border.

"One way or the other, we're going to get a wall. We're going to get a barrier," he vowed Friday.

For news and analysis on the week ahead, don't miss Margaret Brennan (@margbrennan) this Sunday on "Face the Nation" (@FaceTheNation).

We'll hear from Sen. Rand Paul (@RandPaul), R-Ky., a key conservative voice on the Foreign Relations and Homeland Security Committees.

We'll talk also to Paul's Democratic colleague on the Foreign Relations Committee, Sen. Chris Coons (@ChrisCoons) of Delaware.

Rep. Liz Cheney (@RepLizCheney) is the next chair of the House Republican Conference and sits on the House Armed Services Committee. We'll question her.

And as is "Face the Nation" year-end tradition, we'll turn to a panel of CBS News correspondents for perspective on the week (and year) that was:

• Major Garrett (@MajorCBS), CBS News Chief Washington Correspondent
  
• David Martin (@CBSDavidMartin), CBS News National Security Correspondent
  
• Jeff Pegues (@jeffpeguescbs), CBS News Chief Justice and Homeland Security Correspondent
  
• Paula Reid (@PaulaReidCBS), CBS News Correspondent
  

On television, the radio, and streaming online, don't miss America's premier public affairs program this weekend. Click here for your local listings.

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