If Republicans are smart, they’ll outline a series of broad policies relating to tax-code reform on which they can all agree.

Republican euphoria is well deserved. The all but uniform shift among voters toward Republicans in last night’s elections delivered not just the White House but a number of down-ballot victories that seemed out of the GOP’s reach just last week. It was a classic wave election in which almost all hotly contested races fell into one column — a victory rendered even more satisfying by the degree to which the public polling didn’t see it coming.

For Republicans, these are heady days. As such, they will be filled with wild-eyed fantasizing about all the things Republicans can do with their power that they hadn’t allowed themselves even to consider previously, lest they tempt the Fates. That satisfaction is likely to be fleeting. In short order, Republicans will remember that they, with their likely unified control of the federal government, will be solely responsible for rewriting the American tax code when the 2017 Tax Cuts and Jobs Act expires next year.

Few Republicans seem to have grappled with the degree to which this project will suck all the oxygen out of the House and Senate chambers in 2025 and consume the national conversation. The tax code is not some boutique issue — it affects everyone. The debate over it will generate intense public interest and provide Democrats with fertile soil to begin recultivating its voting base. More ominously for Republicans, it is likely to expose the profound ideological tensions within their own coalition.

In short order, the entirely intramural GOP debate over U.S. tax policy is likely to evolve into a contest over first principles. The old guard — the supply-siders and pro-growth tax-cutters — are likely to try to preserve much of the structure Paul Ryan bequeathed to them. But the populist wing of the GOP — its ascendant faction, to which the president is beholden — has other ideas. There is no more effective vehicle for passive social engineering than the tax code, and Republicans who have shed their distaste for big government will seek to use it to contrive social outcomes they desire.

These two visions are incompatible, though they can be synthesized in a document as sprawling as America’s progressive taxation system. But that is precisely the sort of compromise that maximalists resent, and the GOP is not going to have a House majority big enough to mollify its most recalcitrant dogmatists regardless of their respective ideological priors.

If the GOP holds all the House races where its candidates are currently leading, it will enter 2025 with about 220 seats, give or take. As the last two years have amply demonstrated, this is not a recipe for a functioning majority. Exogenous events, external influences, and the unpredictability of the party’s president will scuttle even the best-laid plans. Donald Trump campaigned against his own tax bill, insofar as he promised to reintroduce the state and local tax deduction enjoyed by homeowners in high-tax blue states, to say nothing of all the other revenue generators (taxes on tips, Social Security benefits, etc.) that he’s promised to dispense with. Republicans will have a hard time making Trump’s will manifest, and the dysfunction this process is likely to produce will make Democrats appear more capable and organized if only by comparison.

If Republicans were smart, they’d outline a series of broad bullet points relating to tax-code reform on which they can all agree. And they’d spend the next several months repeating them to the point of exhaustion if only to prime the broader electorate, to say nothing of the party’s ideologically heterogenous “base,” for what’s coming. If the GOP passes on that opportunity and allows tax-code reform to sneak up on them, they may find that it sets a tone for the next Congress and the next administration that voters will be inclined to punish in 2026.