washington <u+2014> on the morning of nov. 8, republicans in the nation<u+2019>s capital were grim-faced and resigned to hillary clinton<u+2019>s impending triumph, hoping only that donald j. trump wouldn<u+2019>t lose so badly as to cost the party the senate. by midnight they were in ecstasy, as it became apparent that mr. trump would take the presidency and republicans would maintain majorities in both houses of congress. a few months from now, it<u+2019>s all but certain that mr. trump will nominate, and the senate will confirm, a new conservative supreme court justice. at that point, republicans will control all three branches of government. the republican party has rarely won this trifecta of power. in fact, over the past seven decades, republicans have controlled the presidency and both houses of congress for a grand total of six years: two during the presidency of dwight d. eisenhower and four under george w. bush. republicans now have an unusual opportunity to achieve their goals. but they aren<u+2019>t accustomed to exercising control of government, and the conservative ideology that pervades much of the party is based on the belief that government is the enemy. what will republicans do with their newfound power? and how will the exercise of that power change the party? it doesn<u+2019>t require a huge stretch of the imagination to envision mr. trump<u+2019>s trying to use the power of the presidency to punish his enemies, withdraw from military and diplomatic alliances, start trade wars, and engage in a wide-scale roundup of illegal immigrants that would call to mind operation wetback in the 1950s crossed with the internment of japanese-americans during world war ii. however, such a divisive policy inevitably would split the country and the republican party as well, leading to a crushing loss in the 2018 midterm elections. if mr. trump wants to be popular (and we know that he does), and if he wants a shot at winning re-election in 2020, he will follow a more prudent course. that doesn<u+2019>t mean that he is likely to govern as a moderate, particularly in the months following his inauguration. one thing that has united republicans over the past eight years is opposition to president obama. president trump is likely to spend his first days in office undoing his predecessor<u+2019>s executive orders on climate change, gun control, financial regulation and anti-deportation protections for the children of undocumented immigrants. (mr. trump may not pursue those children, but he won<u+2019>t protect them.) the iran nuclear deal and trade agreements are also top candidates for repudiation. while republicans can<u+2019>t issue a roman-style damnatio memoriae effacing mr. obama<u+2019>s name and image from the historical record, they will do all they can to erase his legacy. this won<u+2019>t do much to encourage bipartisanship and healing. but republicans may be forced against their will to embrace mr. obama<u+2019>s overarching emphasis on national unity and even some of his policy emphases. party strategists are well aware that the g.o.p. has now lost the popular vote in six of the last seven elections. despite mr. trump<u+2019>s ability to maximize the white vote, and his more surprising ability to bring some minority voters along, it<u+2019>s still not in the party<u+2019>s long-term interest to write off the minorities, particularly hispanics, who are a growing part of the country<u+2019>s population. and a party that<u+2019>s seen to move in the direction of white nationalism will also turn off college-educated white voters, who still form a critical part of the republican coalition. the demands of the g.o.p.<u+2019>s constituents may force a revision on issues such as trade and climate change, particularly if the waters continue to rise in coastal red states like south carolina, georgia and florida. republicans will run into additional difficulties when they try to eliminate mr. obama<u+2019>s signature accomplishment, obamacare. republicans in congress have voted more than 60 times to repeal the affordable care act, but they<u+2019>ve spent far less time thinking about how to replace it. would the 20 million americans who have gained health insurance lose it? would a republican version of the law retain its prohibitions against insurance companies<u+2019> denying coverage to patients with pre-existing conditions? throughout the obama administration, the g.o.p. has had the mind-set of an opposition party, condemning policies without thinking deeply about how to reform them. when republicans have total control of the government, they will bear the responsibility for its failures. perhaps this will encourage a new republican seriousness about policy and an honest attempt to educate their base about the trade-offs inherent in governing. over the past several decades, the republican party has become a coalition of conservative ideologies rather than a coalition of interests. a shared opposition to democrats has helped paper over the contradictions between libertarians, social conservatives, fiscal conservatives and neoconservatives. now that the common enemy has been vanquished (at least temporarily), the rival conservatives will be tempted to go to war with one another. rogue republican factions in congress like the house freedom caucus could even use the threat of a government shutdown or debt default against their own administration. the need to keep order in his ranks may encourage mr. trump to become a richard nixon-style leader, pursuing an agenda that gives enough to each faction that it remains sullen but not mutinous. mitch mcconnell, the senate majority leader, is wary of repeating the overreach that occurred the last time the republicans controlled all three branches. the attempt to reshape the middle east was the most obvious example, but so, too, was george w. bush<u+2019>s push to partially privatize social security. yet mr. mcconnell and others have been promising for years that if the party were given complete control of government, the conservative utopia would follow. the establishment may now be forced, at long last, to stand up to those on the right who are calling for republicans to repeal the institutions of the new deal and the progressive era. much of mr. trump<u+2019>s support, particularly in the swing states of the midwest, came from white working-class voters who missed out on the economic recovery of the past several years and felt victimized by globalization and elites. mr. trump<u+2019>s populism presents a stark contradiction to house speaker paul d. ryan<u+2019>s positions on free trade, immigration and cutbacks in social security and medicare. if the republican party wants to keep its new working-class constituency, it will have to make the economy work for them. the g.o.p. is unlikely to retain these voters if most of the benefits from its tax cuts and other economic policies are seen to go to the party<u+2019>s most affluent supporters. one split that<u+2019>s likely to develop will be over how long the party is expected to maintain its control over the government. those who anticipate only a two- or four-year window will press for the rapid enactment of a maximalist conservative program, even at the risk of an intense backlash. others, however, will focus on the long game. they<u+2019>ll try to build an enduring republican coalition by doing everything possible to increase productivity and stimulate broad-based economic prosperity, and they<u+2019>ll enact legislation that can command at least some degree of bipartisan support. such an agenda would begin with mr. trump<u+2019>s ambitious goal of leveraging as much as a trillion dollars to rebuild our deteriorating infrastructure. mr. trump will not be able to bring back the manufacturing jobs he promised, but he could put his supporters to work building roads and bridges instead. republicans could also take a page from mr. ryan<u+2019>s playbook to encourage private sector investment in distressed communities and retrain unemployed workers in the skills needed for advanced manufacturing. other policies aimed at improving life for working-class americans could include efforts to combat the epidemic of opioid addiction and improve our mental health system. mr. trump said in his acceptance speech that he wanted to <u+201c>bind the wounds<u+201d> opened, in part, by his campaign; he could do so by following the counsel of the national greatness conservatives who flourished briefly in the late 1990s. long before mr. trump conceived of his <u+201c>make america great again<u+201d> slogan, these conservatives called for bringing the country together around grand projects. they were inspired by past national missions such as the settlement of the west, the construction of the national highway system and the march of dimes fund-raising campaign, which led to the polio vaccine. they longed for comparable national undertakings that would bring out the best in both citizens and their government. mr. trump could invoke the tradition of national greatness by asking americans to join him in pursuing a cure for alzheimer<u+2019>s disease, which may present the single greatest threat to our physical and fiscal health in the 21st century. or he could rally our national energies around the construction of the world<u+2019>s first driverless highway, or technology to restore full mobility to paralyzed veterans, or a pilgrimage to revive the economically depressed and spiritually despondent regions of appalachia. mr. trump and the republican party should keep in mind that ronald reagan was able to achieve his greatest victories through cooperation and compromise with democrats as well as a concerted campaign to convince the public of the virtues of supply-side economics and small government. the success of mr. trump<u+2019>s administration ultimately will be determined more by its ability to persuade than compel. geoffrey kabaservice, the research director for the republican main street partnership, is the author of <u+201c>rule and ruin: the downfall of moderation and the destruction of the republican party, from eisenhower to the tea party.<u+201d> follow the new york times opinion section on facebook and twitter (@nytopinion) , and sign up for the opinion today newsletter . a version of this op-ed appears in print on november 13, 2016, on page sr1 of the new york edition with the headline: when republicans take power. today's paper | subscribe
when republicans take power
geoffrey kabaservice