Republicans have tried, on and off, to open the Arctic National Wildlife Refuge for oil drilling since the 1980s. The effort has always engendered intense opposition and always been abandoned. A provision for drilling in ANWR is included in the Republican tax bill almost as an afterthought.

Republicans took a constitutional fight against ObamaCare’s individual mandate to the Supreme Court in 2012, and lost. They targeted it in their ObamaCare repeal-and-replace bill earlier this year, and lost. They tried again with a last-ditch “skinny repeal” bill, and lost yet again. Repeal of the individual mandate is also included in the Republican tax bill.

As the year ends, President Trump is compiling a solid record of accomplishment. Much of it is unilateral, dependent on extensive executive actions rolling back President Barack Obama’s regulations, impressive judicial appointments and the successful fight against ISIS overseas. The tax bill is the significant legislative achievement that heretofore has been missing.

For much of the year, Trump’s presidency had seemed to be sound and fury signifying not much besides the welcome ascension of Neil Gorsuch to the Supreme Court. Now it’s sound and fury signifying a discernible shift of American government to the right.

It’s hard to see how a conventional Republican president would have done much better, except if he had managed to repeal ObamaCare, which was always going to be a dicey proposition given the narrow GOP majority in the Senate.

The tax cut is big — $1.5 trillion over 10 years, and even more if you account for the budgetary gimmicks — and has changes that conservative economists have sought for decades, particularly the lower corporate rate (from 35 to 21 percent), the move to a territorial tax system (companies would only be taxed on their earnings in the US) and the business expensing (companies can write off the full cost of new buildings and equipment).

These reforms are arguably as significant on the corporate side as the Reagan reforms of 1981 were on the individual side. They stand a good chance to be enduring, too — it’s unlikely we’re ever going back up to a 35 percent corporate rate or returning to a worldwide tax system.

Trump’s deregulation has been in full gear. The Environmental Protection Agency is unspooling major Obama-era rules, the Waters of the United States and the Clean Power Plan. The FCC reversed net neutrality. The Education Department rescinded an Obama administration Title IX letter that pushed colleges into abandoning due process in sexual-assault cases.

Obama administration rulings that occasioned fierce debates during his time in office have fallen by the wayside with barely a whimper.

Obama blocked the Keystone pipeline to appease environmentalists who vociferously argued the future of the planet was stake. Trump greenlighted it without a fuss. Obama imposed a contraception mandate feminists portrayed as the only obstacle between women and a “Handmaid’s Tale” future. Trump reversed it; contraception is still widely and easily available in America.

Maybe any Republican would’ve done much of what Trump has. But three acts stand out — pulling out of the Paris accords, de-certifying the Iran deal and declaring Jerusalem the capital of Israel. All three demonstrated an imperviousness to polite opinion that is one of Trump’s signature qualities.

The president also began the process of ending the Obama amnesty for so-called DREAMers, and has re-established a baseline of immigration enforcement that has had an instant impact on illegal border crossings.

None of this is to deny Trump’s failings. Congressional leaders often have to work around his shambolic governing style. Next year could bring a bout of protectionism, and his opposition to entitlement reform during the campaign makes it unlikely Republicans will get a handle on spending. His toxic persona could drive a Democratic wave in the 2018 midterms.

Whatever next year brings, though, Republicans aren’t leaving this one empty-handed.

Twitter: @RichLowry