Trump's election portends dramatic changes in American foreign policy

Donald J. Trump will assume the presidency at a time when the United States faces complex foreign policy challenges with enormous stakes. The statements he has made and the positions he has taken while campaigning will be difficult if not impossible to fully implement and most certainly would entail major and dramatic changes in American foreign policy.

We have rising tensions with Russia and China and a Middle East that is volatile and chaotic. North Korea is moving ahead to develop nuclear weapons. International terrorism is rampant. A refugee crisis has unsettled Europe and beyond, producing political and economic uncertainty. Liberal democracy is in retreat across the globe, and America's leadership role is in question.

Trump has staked out positions that would break with the policies of the past several U.S. administrations. He has questioned U.S. commitments to NATO and has suggested a closer relationship with Russia and its leader, Vladimir Putin. He has grumbled about NATO members who don't meet their defense spending targets under the treaty. He has questioned whether we should defend the Baltic republics against Russian intervention.

He has said he wants to dismantle the nuclear arms deal that the U.S. reached with Iran and five allies in 2015, and he appears open to letting Japan and South Korea develop nuclear weapons, upending years of American nuclear nonproliferation policy.

On the environment, he has called climate change a hoax and wants to cancel billions of dollars in American payments to U.N. climate programs.

Trump rejects longstanding fair trade agreements. He has vowed to renegotiate the North American Free Trade Agreement, the trade pact with Canada and Mexico. He wants to impose a large tariff on goods imported from China, ignoring decades of agreements to reduce tariffs.

Trump has said repeatedly he will build a wall on the Mexican border and have Mexico pay for it. He has pledged to deport millions of unauthorized immigrants at a huge cost, including a large expansion of federal law enforcement officers and a multitude of due process legal challenges.

He has called at times for a "complete and total shutdown" of Muslims entering the country and a ban on refugees from Syria, while suggesting he would be less interventionist in the Middle East than the past two administrations.

At the same time, however, he says he will order the military chiefs to come up with a plan in the first 30 days of his presidency to stop ISIS. He has declined to say how we will do that, except to tell supporters he would "bomb the s**t out of" ISIS-controlled oil fields. He supports waterboarding of accused terrorists, claiming that "torture works," contrary to U.S. policy.

All of this has caused deep concern among American foreign policy experts and has panicked many of our allies, who see Trump's positions as threatening the postwar liberal order. They are alarmed by his protectionist leanings, his aggressive rhetoric and his vows to tear up or weaken longstanding agreements. Foreign leaders sense a period of great uncertainty ahead.

Many of Trump's policy prescriptions remain quite vague, with little specificity on how he plans to achieve his goals. He has backed away from some of his most controversial statements but has declined to clarify his views or say exactly what he intends to do. Neither he nor we can disregard what he said publicly during the debates and at his campaign rallies.

Trump is the oldest president-elect ever and the first president-elect never to have held elective office or have served in the military. He has no foreign policy experience, and he will likely have to rely on the team of national security advisers that he will be appointing in the coming weeks. We can anticipate a real struggle within his administration between his campaign team and the Republican Party foreign policy establishment, which opposes many of the positions he laid out.

But he will be the president, and world leaders and foreign policy experts will have no choice but to deal with him. We can expect a long period of trying to work through many intractable problems.

Trump has bragged about being unpredictable. Yet it's not only Trump's unpredictability that will be a factor. We should remember the comment attributed to former British Prime Minister Harold Macmillan. When asked what was most likely to push governments off course, he replied, "Events, dear boy, events."

Trump will face a daunting task to develop and implement effective foreign policy in a highly unstable world. He will find that governing is far more difficult than campaigning and that making pledges, especially in a complex, chaotic world, is nothing compared to fulfilling them.