Senate Majority Leader Mitch McConnell (R-Ky.), Senate Finance Committee Chairman Orrin Hatch (R-Utah) and Treasury Secretary Steven Mnuchin. (J. Scott Applewhite/AP)
Deputy editorial page editor

The supposed price tag for the Republican tax bill is $1.5 trillion over 10 years. Republicans would have you believe that the measure would sprinkle enough magical growth dust throughout the economy to wipe out that cost. Don't believe them, but also: Don't believe for a moment that the bill would cost a mere — mere! — $1.5 trillion. Peel away the budget tricks and it becomes clear that the real price tag would be hundreds of billions of dollars higher.

Which is where "Fiddler on the Roof" comes in — specifically "Sunrise, Sunset." What once was a schmaltzy ballad is now the blueprint for Republican tax gimmickry.

The House and Senate measures differ in details, but both play the same hide-the-cost games to disguise the real price — the House to the tune of $400 billion, the Senate clocking in at $515 billion, according to the nonpartisan Committee for a Responsible Federal Budget. By the way, those numbers understate things, because they don't include the cost of paying interest on the additional debt.

Some provisions have a "sunrise" — that is, they phase in over time. Of those, the priciest is the estate tax. To begin with, the House bill would merely — merely! — double the size of estates exempt from taxation, from $11 million per couple to $22 million. But beginning in 2024, the estate tax would be repealed entirely.

There is zero policy basis for this change. It serves only to display a lower price tag during the initial 10-year window and to mask the real long-term cost. Of the first-decade price tag of $172 billion, according to the congressional Joint Committee on Taxation, all but $39 billion accrues in the second five years.

Next, "sunsets." The opposite of delayed implementation is the pretense that a break once provided to taxpayers will ever be taken away. Thus the House measure hands out a $300-per-adult tax credit — but sets it to end after 2022, shaving $225 billion off what would have been the 10-year cost. The Senate sunsets most of its individual tax goodies — lower rates, doubling the standard deduction and child tax credit — after 2025, "saving" $240 billion.

These sunsets are one reason why many middle-income families whose tax bill would be lower at first would pay more by the end of the decade than if current law were to stay in place.

So either Republicans are lying when they say these taxpayers will be better off — or they are lying about the plan's true cost. But of course there will be a clamor to make the cuts permanent — just as there was with the George W. Bush tax cuts, which played similar games, although not quite on this audacious scale.

Then there is the biggest gimmick of all — think of it not as sunrise or sunset but as an eclipse, obscuring a whopping $462 billion in deficit-financed cuts. That is the cost of assuming that the size of the tax cut should be measured by how it differs from current policy, not from current law, under which many tax breaks are set to expire. In the real world, they end up getting extended, year after year. They are supposed to sunset, but never do.

Yes, but, the cost of making these breaks permanent is not cost-free, as Republicans fantasize in telling themselves that the $1.5 trillion price tag they've allowed themselves isn't really as big as it sounds. You can't "disappear" extra spending, and tax breaks are spending. Think about it: Your weekly grocery budget is $100. You regularly spend $150 at the market. When you sit down to arrange your finances going forward, you've got a choice: Either cut back on the organic raspberries or acknowledge that you're going to be spending $150 from now on. If so, you need to find some way to pay for — or borrow — that extra $50 a week. If you're like the federal government and going into hock to afford the raspberries/tax cuts, your overall debt is going to be higher than you had planned.

The GOP's games are even crazier than this, because its approach pads the baseline with tax breaks that have already expired or have been scheduled to phase down. In other words, they're not current policy at all.

Sunrise, sunset, eclipse. These are music to tax-writers' ears, because they allow them to cram a tax cut that will cost more than $2 trillion into a $1.5 trillion package and pretend it won't really increase the debt. Lawmakers can fool themselves into believing this is fiscal responsibility. Don't let them fool you, too.

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