Just as President Obama put the final signature on the tax deal passed by Congress this week, he raised an issue that has dogged his predecessors in recent years: how to reform the tax code itself.

Back in the 1990s, there were fewer than a dozen short-term tax provisions — including credits for certain business investments, child credits, education deductions, etc. — that had to be re-approved by Congress every year or so.

By this year, that number had topped 140.

And that has to change, according to two Washington veterans — Mortimer Caplin, who ran the Internal Revenue Service under John F. Kennedy, and David Stockman, budget director for Ronald Reagan.