New US Secretary of State Marco Rubio said the Trump administration's foreign policy will be "based on America's interests first."

In a speech following his inauguration on Tuesday, he told ministry employees that US foreign policy would be practical and realistic, saying, "If our interests intersect with the interests of others, we will work with them."

While he stressed that the United States would seek to "prevent and avoid conflicts," he stressed that this would "not be at the expense of our national security, our national interests, or our values."

Rubio took office after the US Senate unanimously approved his appointment.

For Marco Rubio, the easy part may be over. The Senate confirmed him as secretary of state with unanimous support, and Democrats joined Republicans in praising his acumen and wisdom.

Now comes the task that will make or break his presidency: retaining the full support of his new boss, Donald Trump.

Rubio, 53, comes to the job with more experience than Trump’s previous secretaries of state, having spent the past 14 years in the Senate and is intimately familiar with U.S. foreign policy from the Indo-Pacific to the Middle East and Latin America. But that traditional expertise, combined with Rubio’s long-held, hard-right views on Russia, his support for America’s role in NATO, and his fervent proselytizing of Israel and Netanyahu, is what some fear will ultimately make him a target for Trump’s wrath.

On that point, Thomas Shannon, a former U.S. diplomat who worked extensively with Rubio during the Obama and first Trump administrations, said on ABC: “Is Rubio going to face some challenges as he and the president try to come to an agreement on the purpose of American power?” Still, the scene was cordial Tuesday as Rubio took the oath of office. Vice President J.D. Vance, who served alongside him in the Senate, called him a friend and a “bipartisan solution-finder” as he took the oath.

Rubio echoed Trump's comments in his brief remarks, insisting that whatever the administration and the State Department do must make the country stronger, safer and more prosperous.

"If you don't do one of those three things, we won't do it," Rubio said.

He repeated that sentiment more than once when he first appeared at the State Department, telling staff that his job, and theirs, would be to defend and implement Trump’s “America First” policies.

Rubio’s support in Washington has an institutional feel, with many hoping he will prove a steadying figure at a time of global turmoil. In interviews with more than a dozen people, including Republican and Democratic lawmakers, as well as former diplomats and colleagues, he was repeatedly described as the “responsible” choice to represent the United States abroad, a sentiment that is well-known both at home and on the world stage, according to the network.

“I think he’s going to be able to deliver that message, country by country, continent by continent, that’s not negotiable, but also comfortable,” said Sen. Kevin Cramer, a Republican and longtime right-winger from the deeply conservative state of North Dakota. “Not that I’m looking for every other country to be comfortable with us, but in a way that I don’t think is alarming.”

Rubio’s worldview, experts say, has been largely shaped by his own history: He is the son of Cuban immigrants who arrived in Miami in 1956, three years before the Cuban revolution and Fidel Castro’s rise to power that ended U.S. dominance, “with nothing but the dream of a better life,” he testified before the Senate Foreign Relations Committee last week. His father was a waiter and his mother a hotel maid.

“Thanks to them, I had the privilege of being born a citizen of the greatest country in the history of the world,” he said. “And to grow up in a safe and stable home, by parents who made the future of their children the true purpose of their lives.”

The “Only in America” story is one that helped get him elected to public office in Florida, where he worked his way up from city commissioner to the Florida House of Representatives, eventually becoming the first Cuban-American speaker of the state House of Representatives in the history of the legislature.

Rubio is a right-wing hawk, an advocate of American hegemony in the Middle East and a counterweight to China in the region. He is committed to containing Iran, as he told Congress during a hearing on the 15th of this month, that a nuclear-armed Iran with the resources and military capabilities to continue sponsoring terrorism to destabilize the region cannot be tolerated under any circumstances.

These conditions are likely to be part of any future U.S.-Iran deal, to which the secretary of state remains open. However, Rubio’s tough stance on Iran could also face obstacles with some of the more moderate Gulf states, which view Iran differently than they did during Trump’s first term and have taken a more conciliatory tone toward Tehran in recent years.

Rubio’s record of supporting Israel, oppressor or oppressed, including settlements, is impressive and loyal. However, Rubio sees Gulf allies as essential to containing Iran and “key partners in addressing terrorist threats,” as he puts it. He will likely seek to build on the close ties Trump established during his first term with Saudi Arabia and the United Arab Emirates, and to strike a deal between Israel and Saudi Arabia with a Palestinian state as part of a larger regional deal. The senator has championed the deal with Israel as having many security benefits for Saudi Arabia.

Some believe there is room to break with Trump, perhaps early, especially on Ukraine and NATO. For example, during Trump’s 2017-2021 term, Rubio co-sponsored legislation that would have made it harder for Trump to withdraw from NATO, by requiring a two-thirds majority in the Senate to ratify the withdrawal.

Trump has for years criticized NATO member states that have failed to meet agreed military spending targets and warned during the campaign that he would not only refuse to defend countries that are “behind” in funding, but would also encourage Russia to “do whatever they want” with them.

Rubio is a leading China hawk in the Senate, and Beijing imposed sanctions on him in 2020 over his stance on Hong Kong in the wake of democracy protests, provoking China and creating tensions with it.

As for Cuba, Rubio has as much hostility as he has toward the communist government in his home country.