WASHINGTON — The incoming chairman of the House Armed Services Committee blasted President Donald Trump’s plans to terminate Defense Secretary Jim Mattis two months ahead of his planned exit date, calling the decision “reckless” and “a mistake” that would “deny the country an opportunity to have a stable transition."

“It is a mistake for President Trump to deny the country an opportunity to have a stable transition to a new Secretary of Defense in this fashion," said HASC ranking member Rep. Adam Smith, D-Wash., in a statement. Smith will go from the HASC’s top Democrat to its chairman as Democrats take back control of the House in the 116th Congress.

Just days after Defense Secretary Jim Mattis announced he would step down from that post in late February, Trump announced by Twitter he would push the popular Cabinet member out on Jan. 1. The move cuts short Mattis’ tenure by two months, and adds to an acrimonious end of the relationship between the commander in chief and his top military leader.

Though Smith offered mixed praise for Deputy Defense Secretary Patrick Shanahan, who Trump has tapped as acting secretary, Smith signaled the former Boeing executive is not the right person to fill Mattis’ shoes on a permanently.

“Throwing [Shanahan] into the role of acting secretary with no notice in this way unnecessarily places the United States in a riskier position,” Smith said.

“His expertise in management, research and development, acquisition, and procurement are valuable and conducive to the operations of the Pentagon. However, he does not have the comprehensive understanding of global national security threats that Secretary Mattis does,” Smith said.

Smith also added his voice to the chorus of critics of Trump’s seemingly hasty move this week.

“And why must Secretary Mattis leave early? The President has no given no reason why Mattis can’t stay until the end of February as he planned. We face too many challenges and too complex a threat environment to add to our risk by leaving the country without an experienced national security leader in the seat.”

On Thursday, Mattis in a resignation letter told Trump he was making the move to allow the president to find “a secretary of defense whose views are better aligned with yours.”

He said his February departure date was designed to minimize disruption on the department during the leadership transition.

But Mattis’ criticism of Trump’s national security policies in the letter — in opposition to his announced withdrawal of U.S. forces from Syria and his past negative comments towards U.S. foreign allies — clearly irked Trump, leading to the early dismissal.

On Saturday, Trump appeared to fire back at Mattis on social media, tweeting that “when President Obama ingloriously fired Jim Mattis, I gave him a second chance. Some thought I shouldn’t, I thought I should.”

The top Democrat in the Senate, which Trump will ask to confirm his nominee to replace Mattis, criticized the decision to force Mattis out early.

“Now he’s firing Mattis — a man who has spent a lifetime in public service—by January 1? What did Mattis say no to this time?” Senate Minority Leader Chuck Schumer, D-N.Y., said in a Dec. 23 tweet.

Just after Mattis resigned, Schumer told reporters the former chief of Central Command, "was of the few symbols, the few items of strength and stability in this administration. Everything that indicates stability, everything that indicates strength, everything that indicates knowledge is leaving this administration.”

Republicans have so far been muted about the decision to force Mattis out, but there was bipartisan alarm earlier in the week at news of his resignation letter.

Sen. Marco Rubio, R-Fla., said the letter “makes it abundantly clear that we are headed towards a series of grave policy errors which will endanger our nation, damage our alliances & empower our adversaries.”

“I hope we who have supported this administration’s initiatives over the last two years can persuade the President to choose a different direction,” Rubio added. “But we must also fulfill our constitutional duty to conduct oversight over the policies of the executive branch.”

Mattis is one of several former generals who served in Iraq and Afghanistan who have either departed or is set to depart the administration amid reports of disagreements with the president.

Mattis would join former White House chief of staff John Kelly, who once led the U.S. Southern Command, and H.R. McMaster, a former Army three-star who replaced former national security advisor Michael Flynn, who was fired after lying to the FBI about reaching out to the Russians on the president’s behalf.

Leo Shane III, in Washington, D.C., contributed to this report.

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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