Book income tax is a tax on enterprises who tell people they are profitable. That’s worth something. Cost of enforcement is negligible. Maybe taxpayers will stop seeing overstating earnings as a costfree ploy.
A nominal or low tax on book income, in addition to the standard income tax, corresponds to Jonathan Swift’s notion in Gulliver’s Travels:
When it came to “Ways and Means of raising Money,” in Part 3 of Gulliver’s Travels, among other things, Jonathan Swift suggested, instead of juries, letting the taxpayer himself assess tax, on the honor system. Here’s one example: the “highest Tax was upon Men who are the greatest Favourites of the other Sex, and the Assessments, according to the Number and Nature of the Favours they have received; for which, they are allowed to be their own Vouchers.” Decode the olde English, and you’ve got a tax on either promiscuity or boastful lies about sex — a “Swaggering Stud” tax.
So corporations are either profitable to benefit of shareholders or they’re exaggerating. Either way, a tax seems OK. Adjust the regular tax rate down if people want.
If you follow Swift, book income should be a free-standing tax, not an alternative alternative minimum tax.