President Donald Trump flanked by Secretary of State Rex Tillerson, left, and Defense Secretary Jim Mattis, right, speaks during a Cabinet Meeting in the Cabinet Room at the White House in Washington, DC on Tuesday, Nov. 01, 2017. Jabin Botsford | The Washington Post | Getty Images

Mattis, a former Marine commander with a military career spanning four decades, forged a close relationship with the former Exxon Mobil CEO largely due to their diplomatic approach to national security matters. "We talk two, three times a day, sometimes. We settle all of our issues between he and I, and then we walk together into the White House meetings. That way, State and Defense are together," Mattis said in January. Tillerson and Mattis, along with Treasury Secretary Steven Mnuchin, reportedly had a so-called suicide pact in which the others would resign if Trump tried to remove one of them. As CIA director, Pompeo delivered Trump's intelligence briefing nearly every day and has said that the president "asks really hard questions." Pompeo, 54, became CIA director more than a year ago after serving in the House, where he was a member of the House Intelligence Committee. Below is a roundup of Pompeo's views on various national security matters:

Pompeo on Russian interference in the 2016 presidential election

US President Donald Trump and Russia's President Vladimir Putin at the APEC leaders' summit on November 11, 2017. Mikhail Klimentyev | AFP | Getty Images

While the ongoing investigation continues to determine the extent of Russian meddling in the 2016 U.S. presidential election, Pompeo has downplayed the Kremlin's interference. Speaking at the Washington-based think tank Foundation for Defense of Democracies last year, Pompeo said that the intelligence community determined that Russia's interference ended up not impacting the outcome of the election. However, the intelligence assessment report on this very topic said the community "did not make an assessment of the impact that Russian activities had on the outcome of the 2016 election." And so, Pompeo's comments at FDD were not only a direct contradiction to the report but also in line with Trump's views.

Pompeo on the Iran nuclear deal

Iranian President Hassan Rouhani Getty Images

The staff shakeup installs an ardent critic of the Iran nuclear deal as the nation's top diplomat and narrows the difference of opinion between the White House and the State Department, analysts say. Similar to Trump, Pompeo has called the nuclear agreement "disastrous." In January, Trump said he would stick with the deal for now, but wants to fix the agreement's "terrible flaws." Meanwhile, Pompeo has said that Tehran is "intent on destroying America" and that he was looking forward to "rolling back" the deal. This is why it looks like Pompeo's new assignment is bad news for Iran.



Tillerson's firing also removes another member of the administration's internationalist wing and emboldens Trump to take more punitive measures against rivals, including Iran and Venezuela, they warn.

Pompeo on Guantanamo Bay

A prisoner at Guantanamo Bay, Cuba Getty Images

While serving as a congressman from Kansas, Pompeo criticized the attempt by President Barack Obama to close down the prison at Guantanamo Bay, Cuba. "GTMO has been a goldmine of intelligence about radical Islamic terrorism. I have traveled to GTMO and have seen the honorable and professional behavior of the American men and women in uniform, who serve at the detention facility," Pompeo said in 2016. Pompeo was also against any prisoner transfers from Guantanamo saying, "The detainees at GTMO are treated exceptionally well, so well that some have even declined to be resettled, instead choosing to stay at GTMO." He added: "It is delusional to think that any plan the president puts before Congress to relocate radical Islamic terrorists to the U.S, and potentially Fort Leavenworth Kansas, will make our country safer. The reality is that this proposal will ultimately put Kansans and Americans in danger." It remains to be seen if Pompeo agrees with Trump's push for harsh interrogation techniques such as waterboarding. Trump's pick to succeed Pompeo at the CIA, Deputy Director Gina Haspel, is known for her role in the agency's "black site" prison program, in which terrorism suspects were detained and tortured.

Pompeo on the NSA's spying program

The National Security Agency (NSA) logo is shown on a computer screen inside the NSA in Fort Meade, Maryland. Brooks Kraft | Corbis | Getty Images