The late Democratic governor of New York Mario Cuomo famously remarked about political promises that you campaign in poetry but govern in prose. Donald Trump campaigned in tabloid headlines. There were promises to "Make America great again" and cries of "Build that wall", "Drain the swamp" and "Lock her up!" from his supporters. Now Trump has 10 weeks to prepare before the inauguration that will make him the 45th president of the United States – at which point his governance may indeed begin to seem like turgid prose to his restless anti-establishment base.
For a political novice, fulfilling these bold promises may prove tricky, even with the Republican Party in control of the White House and both houses of Congress for the first time in a decade. The New York businessman, driven by braggadocio and bombast in his campaign, will want to make a success of Trump Republicanism for it to amount to something more than angry election rhetoric.
Trump is the barking, snapping dog who caught the car, and he will be keen to do more than just chew on a tyre. That will require the support of the highest-ranking Republican in Congress, Paul Ryan, speaker of the House of Representatives and a man Trump clashed with repeatedly during the campaign.
“He just earned a mandate, and we now have a unified Republican government,” Ryan said after Trump’s election, taking care to praise the outsider responsible for “the most incredible political feat” he had ever seen. Trump must show that he can deal with people who fall foul of him. In Congress, where he hopes his plans will become a reality, there is a long line of them.
Congressional staffers believe that his desire to score achievements will force the self-professed negotiator to broker deals. “Trump’s ego is so big that he won’t want to end up being the worst president ever. He is not going to be a crazy man,” said one Republican staffer on Capitol Hill who did not support Trump.
His victory on Tuesday and his having Congress behind him mean that the United States is heading into a time of significant policy change after six years of gridlock. “What we don’t know is exactly what the changes will look like,” says John Hudak, a senior fellow in governance studies at the Washington-based Brookings Institution. “We have an idea of some things that Trump supports and that he and the Republican Congress support, but his campaign was very thin on ideas, so we don’t fully understand or know what direction he wants to take the country in a variety of areas.”
So what could happen on Trump’s controversial-policy front? Quite a lot, actually. He could tear down the signature achievements of Barack Obama’s eight-year presidency.
US supreme court
Top of Trump's in-tray is the appointment of a new justice to the US supreme court. Senate Republicans blocked Merrick Garland, Obama's nominee to fill the seat left by the death of the conservative justice Antonin Scalia, in February, so Trump has a spot to fill. During the campaign he posted a list of 21 judges, none of whom will appeal to many liberals. Given the age profile of the court – three of the justices are 78, 80 and 83 – Trump may have more appointments to make, potentially turning conservative for a generation a bench that has to deal with contentious social issues.
This is the lowest-hanging fruit for President Trump and the biggest threat to the Republic of Ireland from his new administration. Democrats and Republicans generally agree that tax reform is needed but disagree about how to go about it or how far corporate taxes should be cut.
Trump has promised the biggest cuts since Ronald Reagan was president. He wants to reduce taxes for American companies to 15 per cent or so, from the current 35 per cent, and block corporate inversions, where US companies take over smaller rivals in low-tax countries such as Ireland, then move their legal headquarters to those new locations.
Stephen Moore, Trump's senior economic adviser, says that the tax cuts are part of a plan to bring back multinationals and create new American jobs in the industrial north and midwest, which heavily backed Trump: "You are going to see a flood of companies leaving Ireland and Canada and Germany and France, and they are going to come back to the United States."
Trump has called President Obama's healthcare reform, a signature achievement of his first term, a total disaster. Dismantling a scheme that insures 20 million people may be tricky, despite Republican fury about rising premiums that helped Trump win swathes of votes across the economically depressed rust belt.
Republicans do not have the 60 votes in the Senate to overturn Obamacare, but the party could use budgetary measures and its 51 seats, of the 100 in the chamber, to tinker with the funding of the healthcare scheme. Millions more people are due to be covered under Obamacare next year, so trimming around the edges may be possible, too.
The US-Mexico border
Leaving aside the question of whether a 10m-15m wall is necessary along more than 1,500km of the United States' border with Mexico, the proposal is meeting resistance in Congress not least because of its likely cost.
Trump has said that he would make Mexico pay for the wall, but the country has said that it has no intention of footing the bill. The Republican has also said that he could find a way of taxing remittances – cash sent to Mexican families by relatives in the US – to force Mexico’s hand.
Estimates of the cost of the wall vary from Trump's own range of $8 billion to $12 billion right up $42 billion for a lower wall, about 8m high. These costs would face stiff congressional opposition if the US had to cover them. The former New York mayor Rudy Giuliani has said that Trump could build a wall without authorisation from Congress, by redirecting money from the US immigration service. "It's a campaign promise," he explained. "He's not going to break a campaign promise."
Ban on Muslims
Mention of Trump's proposal to temporarily ban Muslims from entering the United States briefly disappeared from his website this week, leading to speculation that he may have dropped one of the most divisive ideas of his campaign. The ban has shifted more recently to a geography-based bar, suspending immigration "from any nation compromised by terrorism". Trump could redirect immigration resources to make this happen.
Deportation of illegal immigrants
Most of the United States' 11 million undocumented immigrants have been in the country for more than five years, which means they are entitled to a court hearing before they can be deported. This would jam up the legal system and stymie Trump's plans for a deportation force. In his proposals Trump promised to deport illegal criminals first, remaining vague about how he would treat others, including thousands of Irish.
As with many other issues, he will need congressional approval to push through his immigration plans, although he can make other changes through executive action. He could, for example, follow through on his promise to end Obama’s scheme that protects illegal immigrants who came to the US as children, by assigning immigration- and customs-enforcement agents new priorities, as Obama did.
Trump won over frustrated blue-collar workers in big numbers by bashing trade pacts such as the North American Free Trade Agreement – "the worst trade deal maybe ever" – and the proposed Trans Pacific Partnership with 11 Pacific Rim countries.
Under a plan that Trump's transition team has devised to tackle "job killing" trade policies, the new president could decide to withdraw from the Trans Pacific Partnership within his first 100 days in office and threaten to end US involvement in Nafta 100 days after that unless key demands are met. Canada and Mexico are willing to discuss the tripartite 1994 free-trade pact, as they fear that they could otherwise be shut out of the US market.
Trump, who has described climate change caused by humans as a hoax, could weaken Obama's environmental regulations and forgo US domestic commitments to the Paris climate agreement, a deal he has promised to cancel. Meeting his pledge to restore Appalachia's coal industry and bring jobs back to the area, Trump could dismantle Obama's Clean Power Plan regulations, one of the current president's proudest achievements.
Iran nuclear deal
The president-elect called the July 2015 pact to curb Iran's nuclear programme a disaster and "the stupidest deal of all time". The agreement was reached with the United States and five other countries: Russia, Britain, France, Germany and China. The Trump administration could walk away from it, but it is complicated.
US allies in Europe, along with Russia and China, have begun to do business with oil-rich Iran, and some European sanctions that forced the Iranians to the table have already been lifted. Newt Gingrich, the former speaker of the House of Representatives, and a contender to be Trump's secretary of state, has said that he would renegotiate it.
Investigating Hillary Clinton
During the second presidential debate Trump threatened to appoint a special prosecutor to investigate Hillary Clinton and her use of a personal email server if he was elected. His campaign manager Kellyanne Conway did not rule that out this week, saying on Wednesday that the issue would be discussed "in due time".
If the president-elect’s focus is on uniting the country, this may further alienate people who did not vote for him. But if he chooses to govern in tabloid headlines a prosecution of his defeated opponent would quell the anger of his core supporters.