If he is confirmed as secretary of state, Rex Tillerson may come to look back wistfully at the relative simplicity of life as an oil executive.

As ExxonMobil’s boss, Tillerson has the task of maximising profit on behalf of his shareholders. No other benchmark of success really matters, and it can be measured by anyone who can count dollars by the billion. Success as the nation’s top diplomat will be harder to assess. What price is to be put on “US values” – human rights, and what is the rate of exchange of those objectives with national security? There will be no shortage of opponents and rivals, in his own administration and probably in his own department, who will be counting minuses where he sees pluses or using entirely different units of measurement.

There is rarely just a buyer and seller in diplomacy. In the many global crises that await Tillerson and all those still to come that will rear up in his face, there will be a tangle of interlocking interests that defy “dealmaking”. That is especially true in a situation where some of the main elements of Trumpian foreign policy contradict one another. The in-tray will be overflowing and messy.

'Friends forever'? China wary of Rex Tillerson wooing away Russia Read more

North Korea

Kim Jong-un’s regime in Pyongyang is working towards the capability to put a compact nuclear warhead on a long-range missile that can reach the US west coast. Any military attempt to pre-empt its progress is likely to draw a ferocious, and probably nuclear, response, aimed at US allies and bases in the region. Aware of this, one of those allies, South Korea, may start to consider building its own bomb if it feels US commitment to its defence is weakening. Trump has indicated he wants to solve the problem by having China put pressure on North Korea. As secretary of state, Tillerson would have to figure out how to pursue that policy while at the same time addressing another Trump priority: confronting China.



China

Trump has already triggered a crisis in US-China relations during the transition by talking to the Taiwanese president and casting doubt on the 37-year-old One China policy that withholds recognition of Taiwan’s independence. Beijing has signalled that it would respond dramatically if the One China principle is abandoned. The fury of the reaction could be compounded if Trump carries out his threats to declare China a “currency manipulator” and therefore impose heavy tariffs on Chinese imports. Early on in the administration, Tillerson is likely to be called on to prevent the crisis turning into a trade war or worse, in the knowledge that Chinese and US forces are already brushing up close to each other in the South China Sea.

Europe, Nato and Russia

Washington’s oldest allies in Europe are deeply nervous about Trump’s ties to Moscow, his commitment to fulfilling US obligations to Nato and his attitude towards the European Union, given his enthusiasm for Brexit and links to the European hard right. The anxiety will have been amplified by Tillerson’s own history of Kremlin hobnobbing, and fears that a businessman’s transactional approach would lead to bargaining away collective security at the edges of the alliance and drifting towards Moscow’s agenda of reestablishing a sphere of influence in eastern Europe. Most European governments are seeking an unequivocal statement of faith in the EU and Nato, and a united front against Moscow over its military intervention in Ukraine until it abides by the Minsk agreement on defusing the conflict. Will Tillerson’s boss be prepared to give these assurances? If not, there will be a lot of fallout to manage.

Facebook Twitter Pinterest Vladimir Putin presents Rex Tillerson with the Order of Friendship at the St Petersburg economic forum in June 2013. Photograph: Mikhail Klimentyev/Tass

Iran

The national security leaders Trump has picked so far are determined to push back against Iran’s influence in the Middle East, its support for militant groups and its missile programme. There is strong support in Congress for such a policy. The open question is whether it should involve Washington walking away from last year’s nuclear deal. That could lead to Iranian retaliation, declaring itself no longer bound by the agreed curbs on its nuclear activities. If it aggressively pursued uranium enrichment, that would put the prospect of war back on the table. US abrogation of the deal would also create a rift with the western Europeans, Russia and China, the agreement’s co-signatories, which would have to be managed. It would undermine faith in the value of a US signature on agreements, weakening efforts to reach a nuclear or missile agreement with North Korea, for example.

Syria and counterterrorism

The direction that Trump and his incoming national security adviser Michael Flynn have mapped out in Syria is aimed at a purely counter-terrorism approach, involving possible cooperation with Russia and the Syrian regime. A number of unanswered questions about this policy would have to be resolved from the start and most likely the secretary of state would be asked to do the resolution. Firstly, making common cause with two parties responsible for indiscriminate mass bombing of civilians and potentially many other war crimes would appall some European allies and provide a powerful recruitment tool for jihadists in Syria and around the world. It would also involve military cooperation with Iran and furthering the Iranian strategic aim of carving out a corridor from Iran to Lebanon, which runs counter to the strategic aim of pushing back Tehran’s influence. That would run into heavy resistance in Congress and in the Pentagon, where any collaboration with Russian forces would require a special waiver from the defence secretary, James Mattis. In this matter, and many others, Tillerson would require diplomatic skills inside Washington as much as he would need them abroad.