James Buchanan discusses three ideas for Constitutional amendments. He proposes an amendment to require balancing the Budget, and amendment forcing laws to be nondiscriminatory, and an amendment against regulating voluntary market transactions. On the nondiscrimination issue, he writes,
The American structure will not survive if “democratic politics” comes to be interpreted as overt conflict among parties and groups each seeking to further particular interest.
...A nondiscrimination amendment might, however, offer the basis for the replacement of the complex tax structure by a uniform rate of tax that is imposed on all income, without exemptions, deductions, credits, or other special treatments. On the spending or outlay side of the budget, the generality norm would require that program benefits be extended across all members of the polity.
I have a difficult time envisioning how a nondiscrimination amendment would work in practice. Perhaps some more examples would help to explain.
This afterthought also caught my eye:
constitutional changes that may have been made imperative with the emergence of terrorism, both in the enabling of effective prevention and in the control of possible abuses of authority.