WASHINGTON • The US Senate confirmed former ExxonMobil chairman and chief executive Rex Tillerson in a 56-43 vote to become the nation's 69th Secretary of State just as serious strains have emerged with important international allies.
The votes against Mr Tillerson's confirmation were the most in Senate history for a secretary of state, a reflection of Democratic unease with US President Donald Trump's foreign policy pronouncements that threaten to upend a multilateral approach that has guided US presidents since World War II.
In a brief swearing-in ceremony in the Oval Office on Wednesday, Mr Trump said that Mr Tillerson understood "the importance of strengthening our alliances and forming new alliances to enhance our strategic interests and the safety of our people".
Mr Trump's unapologetically nationalistic approach has put into question the value of many of the alliances and multilateral institutions. How Mr Tillerson translates Mr Trump's vow of "America First" into the kind of polite diplomatic parlance that will maintain vital ties will be a significant test.
Among his other challenges are dealing with Mr Trump's promises to recast relations with China and Russia, move the US Embassy in Israel to Jerusalem from Tel Aviv and re-examine an international nuclear deal with Iran.
In a White House briefing on Wednesday, Mr Michael Flynn, the national security adviser, issued a stern warning to Iran. "The Obama administration failed to respond adequately to Teheran's malign actions," he said.
With operations on six continents, ExxonMobil is in some ways a state within a state. As its chief executive, Mr Tillerson, 64, struck deals with repressive governments - in at least one case, against the advice of the State Department. But some experts said they welcomed his selection in the hope that he would bring ballast to a turbulent administration.
"Rex Tillerson will have the most demanding and complex agenda to face a secretary of state in a very long time," said Mr R. Nicholas Burns, a Harvard professor and career foreign service officer.
Mollifying vital allies infuriated by Mr Trump's orders could be a full- time job. A ban on refugee arrivals and entries from seven Muslim- majority countries, for instance, has enraged Iraqi officials, whose cooperation is vital in the fight against the Islamic State in Iraq and Syria.
The ban has also infuriated many European leaders crucial to efforts not only in Syria, but Afghanistan and Libya as well, and it has tarnished what had been viewed as a successful trip by Prime Minister Theresa May of Britain, who on Monday said she opposed the ban.
Relations with Mexico have plunged to their lowest level in decades after Mr Trump insisted that he would build a border wall regardless of Mexican opposition.
The relationship with Chancellor Angela Merkel of Germany threatened to become toxic after Mr Peter Navarro, the director of Mr Trump's new National Trade Council, denounced the relatively low value of the euro as an unfair currency advantage for Germany.
Mr Ryan Crocker, who served as the US ambassador to five Muslim countries, said: "Tillerson faces the most difficult task of any secretary of state in the post-war era in trying to reconcile President Trump's intention to make a radical break from decades of bipartisan consensus US foreign policy leadership with the reality that, if he succeeds, such a break could lead to global chaos."
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