John Bolton replacing H.R. McMaster as Trump national security adviser

President Trump ousted White House National Security Adviser H.R. McMaster on Thursday and hired former Ambassador John Bolton, a conservative who takes a harder line against Iran and the Obama administration’s oft-criticized nuclear deal.

The president announced the long-expected move on Twitter.

“I am pleased to announce that, effective 4/9/18, @AmbJohnBolton will be my new National Security Advisor,” Mr. Trump tweeted.

He added, “I am very thankful for the service of General H.R. McMaster who has done an outstanding job & will always remain my friend. There will be an official contact handover on 4/9.”

Aides said it was a “mutual” decision between Mr. Trump and Gen. McMaster, a three-star Army lieutenant general who has counseled the president against ripping up the Iran nuclear deal. As speculation mounted last week about Gen. McMaster being forced out, he told a reporter, “Everybody’s going to leave the White House sometime.”

Mr. Bolton visited the White House for a final job interview Thursday afternoon.

“It’s obviously a great honor,” he said on Fox News Channel, where he has been a contributor. “It’s still sinking in.”

The change in the key national security post will take place before Mr. Trump is scheduled to hold a high-stakes meeting with North Korean leader Kim Jong-un sometime in May over denuclearization. The president is also facing a May 12 congressional deadline for recertifying that Iran is complying with the nuclear deal that has given Tehran relief from international economic sanctions in return for limits and inspections on its nuclear program.

A White House official said the president and Gen. McMaster “mutually agreed” on his resignation, and that Gen. McMaster will retire from the Army. Earlier, White House aides had talked of the possibility of moving Gen. McMaster to the Pentagon for a soft landing and a fourth star.

“The two have been discussing this for some time,” the official said. “The timeline was expedited as they both felt it was important to have the new team in place, instead of constant speculation. This was not related to any one moment or incident, rather it was the result of ongoing conversations between the two.”

The president said in a statement that Gen. McMaster “has served his country with distinction for more than 30 years.”

“General McMaster’s leadership of the National Security Council staff has helped my administration accomplish great things to bolster America’s national security,” the president said. “He helped develop our America First National Security Strategy, revitalize our alliances in the Middle East, smash ISIS, bring North Korea to the table, and strengthen our nation’s prosperity.”

Conservatives also have targeted Gen. McMaster over his decision in 2017 to extend a security clearance for Susan Rice, President Barack Obama’s final national security adviser, who was accused of mishandling classified information involving Trump campaign officials.

Gen. McMaster said he requested retirement from the Army effective this summer, “after which I will leave public service.”

“Throughout my career it has been my greatest privilege to serve alongside extraordinary servicemembers and dedicated civilians,” he said. “I am thankful to President Donald J. Trump for the opportunity to serve him and our nation as national security advisor. I am grateful for the friendship and support of the members of the National Security Council who worked together to provide the president with the best options to protect and advance our national interests.”

Mr. Bolton will be the president’s third national security adviser in 14 months. Michael Flynn resigned in February 2017 after misleading Vice President Mike Pence about the extent of his contacts with Russia’s ambassador to the U.S. before the inauguration.

The president’s move extended a series of high-level staff shake-ups in the administration. Mr. Trump fired Secretary of State Rex W. Tillerson last week, replacing him with CIA Director Mike Pompeo, who, unlike Mr. Bolton, must be confirmed by the Senate.

White House Communications Director Hope Hicks, one of the president’s most trusted aides, resigned last month.

With Gen. McMaster’s departure, the president has had turnover of 48 percent in key West Wing posts in just 14 months, according to research by the Brookings Institution.

Mr. Bolton, currently a senior fellow with the American Enterprise Institute, has long been regarded by the left as a combative neoconservative, but he has for years garnered the support of GOP hawks by advocating publicly and aggressively for Washington to clarify who its enemies are and to be on a war footing against such rogue nations as Iran and North Korea.

In an op-ed in The Washington Times in July 2017, Mr. Bolton wrote that he had been arguing “for over 10 years” that “the declared policy of the United States of America should be the overthrow of the mullahs’ regime in Tehran.”

His rhetoric on North Korea has been similarly aggressive. Writing in the Wall Street Journal in February, Mr. Bolton argued that despite North Korea’s “propaganda” around recent diplomacy with South Korea, the nuclear threat emanating from Pyongyang remains “imminent” and that Washington should seriously weigh a pre-emptive military strike against North Korean nuclear facilities.

“Given the gaps in U.S. intelligence about North Korea, we should not wait until the very last minute,” Mr. Bolton wrote. “That would risk striking after the North has deliverable nuclear weapons, a much more dangerous situation.”

Some Republicans hailed his appointment.

“I know John Bolton well and believe he is an excellent choice who will do a great job as national security adviser,” said Sen. Marco Rubio, Florida Republican. “General McMaster has served, and will continue to serve, our nation well and I thank him for his service.”

The Republican Jewish Coalition also praised the move.

“Ambassador Bolton is a true patriot, with a long history of standing up to Iran and other rogue nations, and has demonstrated an ironclad commitment to our unshakable bond with Israel,” the group said. “Ambassador Bolton’s decades of foreign policy and diplomatic experience will serve him well in this important role.”

Democrats and human-rights groups blasted Mr. Bolton’s appointment, raising his role during the Bush administration in claiming that Iraq had weapons of mass destruction, a justification for war that turned out to be untrue.

“Appointing John Bolton to be national security advisor is a grave danger to the American people and a clear message from President Trump that he is gearing up for military conflict,” said Sen. Edward J. Markey, Massachusetts Democrat and a member of the Senate Foreign Relations Committee. “John Bolton played an instrumental role in politicizing the intelligence that misled Congress and the American people into going to war in Iraq. He supports proactively bombing Iran, conducting a first strike on North Korea without provocation, and has said, ’There is no such thing as the United Nations.’ Mr. Bolton has never seen a military conflict he didn’t like.”

Mr. Markey added, “President Trump is endangering the American public by appointing this extreme war hawk as his chief advisor on national security matters. John Bolton has already blundered the United States into one terrible conflict; we cannot let him do it again.”

Another Democrat on the Senate Foreign Relations Committee, Sen. Chris Coons of Delaware, said Mr. Bolton’s positions on North Korea’s and Iran’s nuclear programs “are overly aggressive at best and downright dangerous at worst.”

Amnesty International said it’s concerned that Mr. Bolton “generally disparages international law” and that his appointment could thwart human-rights groups’ efforts to “prevent unlawful killings and end unlawful detentions at Guantanamo,” the terrorist detention facility in Cuba.

In his interview on Fox News on Thursday night, Mr. Bolton said his policy positions expressed as a private citizen won’t necessarily carry over into the Trump administration, and that Mr. Trump’s decisions will be final on any issue.

“What I’ve said in private is now behind me,” he said.

He also said part of his role will be to make sure that federal bureaucrats carry out the president’s decisions effectively.

“I’ve seen the way that bureaucracies that don’t like decisions sit on them,” Mr. Bolton said.

He said he was “outraged” by a White House leak this week in which someone revealed that Mr. Trump went against staff’s written advice not to congratulate Russian President Vladimir Putin on his re-election.

“It’s completely unacceptable,” he said. “You cannot expect other foreign leaders to be candid and open in their conversations with the president if some munchkin in the executive branch decides they’re going to leak the talking points or the transcript. They should be ashamed of themselves.”

Mr. Bolton also served as U.S. ambassador to the United Nations from 2005 to 2006 in the administration of George W. Bush, and as undersecretary of state for arms control and international security from 2001 to 2005.