In Greek drama, a tragic flaw is a defect so severe that it leads to downfall.
A tax cut measure championed by Republican lawmakers and approved during the legislative session contains such a flaw. Specifically, the measure would repeal the tax exemption for prescription drugs.
When the flaw was discovered after the session ended, Republicans argued it doesn't matter. They said the provision was unintended and they could repair the flaw next session if Gov. Jay Nixon would sign the bill into law.
The Democratic governor - no fan of the tax cut - stamped it with a veto. His veto message included a harsh characterization of the measure as "an ill-conceived, fiscally irresponsible experiment."
With the September veto session drawing nearer and a close vote anticipated, battle lines are being drawn.
Fueled by $2.4 million from conservative political activist Rex Sinquefield, Republicans have created a media campaign. The message is Missourians deserve a tax cut, but they must remove the veto obstacle by contacting their legislators and encouraging an override.
Not to be out-flanked, Nixon has embarked on a campaign of his own.
In Eldon on Tuesday, he cited a study showing aid to public education would be reduced if his veto is not sustained. The governor previously has criticized the proposal, pointing out that Missouri already is a low-tax state and contending the loss of revenue that lawmakers predict is artificially low.
Republicans argue the tax cut proposal includes a provision to help safeguard income by linking corporate and individual tax rate reductions to state revenue growth.
These points and counter-points might make for a pretty close call, were it not for the tragic flaw of permitting a tax on prescriptions, which Missourians have not had to pay since 1979.
And the Republican argument to pass it now and fix it later is hollow.
Because history has shown that no agreed-upon fix is a sure thing in the Missouri Legislature. Any bill enjoying bipartisan consensus is a magnet for attachments and amendments.
A recent example was the measure to extend closure of security plans for public buildings, including schools. The popular bill was laden with extras and bogged down for much of the session. It finally was approved in the waning hours after being stripped of its baggage.
Elected officials generally agree repealing the exemption for prescription drugs is an unintended error. An intentional error would be knowingly approving a flawed bill.