Washington (CNN) If President Donald Trump really wants Secretary of State Rex Tillerson to leave, he'll have to tell him to go.

Defying predictions of his demise, Tillerson is saddling up for another year in Washington and is making clear that leaks and speculation about how long he'll last will not drive him out.

Tillerson has been busy solidifying his position by starting to build the Washington constituency he never had, and showing signs of permanence after surviving one of the most difficult years ever endured by any modern secretary of state.

It might not seem like much, but he's managed to get the White House to sign off on his own pick, career diplomat and China expert Susan Thornton -- an enemy of the populist, nationalist wing of the administration -- as his top official on East Asia. And more of his picks are arriving at Foggy Bottom soon.

Tillerson is opening up to the media, conducting interviews with top outlets while his staff promises more access to a press pack he largely snubbed in his first year in office. And the secretary is telling friends and colleagues that he won't let his West Wing antagonists, who are known to include the President's son-in-law Jared Kushner and national security adviser H.R. McMaster, run him out of town.

And while the unpredictable Trump could again sour on Tillerson at any moment, the secretary of state is making it implicitly clear that only a direct push from the President -- who, despite his "you're fired" mantra, struggles with in person dismissals -- will do it.

"I think we're going to have a very productive 2018," Tillerson told CNN in an interview on Friday . "I intend to be here for the whole year."

Figuring out Washington despite roadblocks

Tillerson's show of stubbornness is perhaps a sign that after struggling to transition from the rituals of the boardroom to the Washington bear pit, he's learning how this town works.

But in keeping with the whiplash style of his leadership, Trump suggested on Saturday, days after mocking Kim over the size of his nuclear button, that he'd be willing to talk to the North Korean leader over the phone, and gave "Rex" a shout out for his work in a possible sign that the secretary of state is making headway.

JUST WATCHED Trump says he would talk with Kim Jong Un Replay More Videos ... MUST WATCH Trump says he would talk with Kim Jong Un 00:59

Among the difficulties that Tillerson endured last year: He had to cede part of State Department's portfolio to Kushner, notably the stuttering Middle East peace effort and, initially at least, management of ties with Chinese President Xi Jinping.

Trump also smacked Tillerson down when he tried to mediate the dispute between Qatar and America's other Persian Gulf allies.

Tillerson's relationship with the President, whom he barely knew when he was asked to be secretary of state, was so obviously strained that most people believed it when he reportedly called the commander in chief "a moron" last year.

His treatment by the White House did not just make him appear a forlorn figure in Washington. It also embarrassed him internationally. While foreign diplomats want to believe that his more moderate approach is the authentic face of American foreign policy, there is plenty of evidence to the contrary.

And Tillerson's alienation of his own department amid savage cost cuts prompted many seasoned diplomats to quit, stoked severe criticism from Foggy Bottom alumni, and left him as a man with few friends in Washington and no personal power base.

JUST WATCHED Tillerson splits from Trump on impact of Russia probe Replay More Videos ... MUST WATCH Tillerson splits from Trump on impact of Russia probe 04:50

'I believe in the Code of the West'

Expectations of his departure were also rooted in the fact that Tillerson hardly needs this. His Texas ranch awaits his retirement. He's rich. And nothing in his gilded four decades culminating in the top job at ExxonMobil prepared him for his rough treatment in the administration.

Yet that Texan heritage may hold a clue to his determination to stay, as he honors what he calls cowboy values of honor and dignity, that seem quaint in the backstabbers' paradise of Trump's Washington.

Explaining how the code of cowboy values underscored his business philosophy, he might have been talking about his relationship with a world leader or even Trump himself.

"The day is going to come when we're going to have some disagreements over this agreement," he said, as if speaking to a dealmaking partner. "And I want to know that you and I are going to work this out. And we'll shake hands on it, and that's all I need to know."

Tillerson, who Trump reportedly picked because his silver coif and well-cut suits made him look the part, has forged a foreign policy path that does not exactly contradict the President's "America First" worldview but sits alongside it, one reason why there is so much global confusion over US strategy.

In the CNN interview, he noticeably did not reaffirm Trump's position that denuclearization is a condition of talks with Pyongyang, despite being slapped down by the White House last month when he suggested talks.

Tillerson laid out an authentically tough policy on Russia. He is, incidentally, praised and admired by Russia specialists on the National Security Council for his tough line, despite Trump's efforts to build a personal relationship with President Vladimir Putin.

He also refuted Trump's claim -- made again Saturday -- that special counsel Robert Mueller's Russia probe is bad for US foreign policy, saying the investigation had not harmed it.

JUST WATCHED Tillerson: Russia made for a difficult year Replay More Videos ... MUST WATCH Tillerson: Russia made for a difficult year 02:23

Throwback to Baker, Rice

By staying in the administration, Tillerson is preserving a voice for a traditional, orthodox Republican foreign policy, balancing out the economic nationalists in the other wing of the administration.

In fact, his philosophy is closer to that of luminaries like James Baker, the former secretary of state, and one of his more recent predecessors, Condoleezza Rice, or former Defense Secretary Robert Gates, who recommended him to Trump. He's often seen as a bulwark of competence and stability in the administration, alongside Defense Secretary James Mattis.

Either of his rumored successors, CIA Director Mike Pompeo or US Ambassador to the UN Nikki Haley, would swing far closer to Trump's worldview than Tillerson, as both have unabashedly, demonstrated to the President.

In some ways, Tillerson's approach is like "cutting" -- a cowboy technique practiced by he and his wife, Renda, to separate a single cow from the herd on the ranch.

Tillerson picks off individual foreign policy issues and works on them before they are eventually reclaimed by the President and his wild West Wing herd.

The White House is in charge

But the preeminence of the White House, coupled by the weakness of the State Department, may be Tillerson's biggest challenge.

However Tillerson tries to safeguard internationalist instincts, Trump still pulled out of the Paris climate accord that the secretary of state supported.

Trump still recognized Jerusalem as Israel's capital against Tillerson's advice.

Trump also decertified the Iran nuclear deal -- though Tillerson is working to try to save it with allies in Congress. The secretary's influence has even been questioned by his few friends in Washington. In October, Bob Corker, the chairman of the Senate Foreign Relations Committee, accused Trump of trying to "castrate" Tillerson.

Ultimately, Tillerson's staying power will depend on his relationship with Trump, which he freely admits is a work in progress.

"We have different management styles. How I make decisions, how I process information," Tillerson told CNN after a week in which a new book by journalist Michael Wolff claimed Trump didn't read and had a minuscule attention span.

"I have to learn how he takes information in and process(es) it and makes decisions, and that's my responsibility," Tillerson said.

"He is not ... typical of presidents of the past; I think that's well recognized," he added. "That's also why the American people chose him. They were tired of what was being done in the past."

So for now, Tillerson stays, even though it still seems doubtful he will serve for Trump's full term.