Trump may not know his Bible much, but he knows his Christian right constituency and keeps his promises to them. Photo: Drew Angerer/Bloomberg via Getty Images

Nestled in the new House tax bill is a provision that doesn’t have a big (if any) impact on federal revenues, raise or lower anyone’s tax rates, or really change much of anything, at least in the short run. Yet it represents a major political payoff by Donald Trump and the Republican Party to a very important electoral constituency: conservative Evangelical clergy. It would repeal the Johnson Amendment, the 1954 law (sponsored by then-senator Lyndon Johnson, who was angry at a right-wing nonprofit group that was attacking him in Texas) that prohibits tax-exempt charitable organizations, including churches, from such partisan electioneering activities as endorsing candidates.

The Johnson Amendment is rarely enforced, and is thus something of a phantom threat. Indeed, once a year since 2008 conservative ministers have held a “Pulpit Freedom Sunday” on which they address blatantly political topics in order to defy the Johnson Amendment, without consequence. But the law has gotten all tangled up in conservative Evangelical paranoia about “religious liberty” being under attack from secular-socialist political enemies. And so Donald Trump made repealing it one of his principal campaign promises to Christian-right activists. It was even included in the 2016 Republican Platform. In his first speech as president to a distinctly religious audience, he amped up the rhetoric, promising to “destroy” the Johnson Amendment, something actually not within his power.

But it is within Congress’ power, which is how it wound up in this tax bill.

It’s an almost entirely symbolic gesture so long as the IRS continues to give churches (and other tax-exempt organizations) that violate the Johnson Amendment a wide berth. It could, however, have a significant impact on campaign-finance practices down the road, if political donors figure out they can get a tax deduction for contributing to churches that intend to spend the money on particular parties or candidates. Last year Emma Green predicted conservative Evangelical churches could wind up becoming “the new super-PACs” if the Johnson Amendment was repealed.

For now, though, the drive to repeal the Johnson Amendment is most notably an example of Donald Trump’s transactional relationship with the Christian right and with white conservative Evangelical voters. He doesn’t much bother to even pretend to share their religiosity, but he does make them very specific political promises — notably turning over his entire judicial vetting process to hard-core conservatives guaranteed to produce nominees like Neil Gorsuch who are reliably aligned with Christian-right views on hot-button constitutional issues — and keeps them. So repealing the Johnson Amendment is just another layer of concrete in the foundation of trust between this heathenish president and his loyal conservative Christian flock.