Jay Cost explains at National Review Online why it’s difficult to entrust tax reform to Congress.

No doubt, tax reform is necessary. Our tax code is a mess, to say the least. But why is it a mess? The answer, at bottom, has to be Congress itself. The legislature is solely responsible for setting tax rates, exemptions, and deductions. It is therefore reforming a tax code that it alone deformed.

To put it bluntly, Congress is not well suited for national economic planning, which is basically what pro-growth tax policies boil down to. As a matter of fact, Congress outsources a lot of economic planning — like environmental regulation — to the bureaucracy, because it knows it is not capable of handling such matters for itself. It keeps tax policy within the legislature primarily because that doubles as a way to distribute political benefits to key constituencies.

The problem is an institutional one. It is really not accurate to say that Congress is a “national legislature,” for there is no member in either chamber who is elected by the nation at large. Instead, it is the meeting place of representatives of discrete geographical constituencies. This inclines the legislature to parochial concerns rather than national ones. …