Republicans made significant progress towards a balanced-budget amendment vote in the debt-ceiling debate.  While Democratic leadership initially mocked the idea, polls showed that voters broadly support a constitutional bar on deficit spending — including wide majorities of Democrats and liberals.  Some Democrats in Congress later expressed support for the concept of a balanced-budget amendment to the Constitution, and a vote on some form of BBA is expected later this year.

But what form will get a vote?  Brent Bozell worries that Republicans might give away the key to controlling tax rates:

The version attached to the House Republicans’ Cut, Cap and Balance bill was sponsored by Sens. Mike Lee (R-Utah) and Orin Hatch (R-Utah). It required a supermajority to use tax increases to balance the nation’s books.

This element is critical. Congress has proven its inability to show spending restraint, especially when there’s a prospect of a tax increase ahead. By raising the bar for passing new taxes through a balanced budget amendment, this dangerous, and irresponsible, option is more difficult to do.

In the back halls of Congress though, there are now whispers that Republicans are considering bringing a “tax increase BBA,” which requires only a simple majority to raise taxes, to the floor. If the GOP goes for a tax increase BBA, not only will they be enabling liberals to make permanent President Barack Obama’s spending binge — highlighted by the failed stimulus and Obamacare — but they will also give vulnerable Democrats political cover to help keep their jobs in November, 2012.

Republicans won’t be so lucky. Many will likely be signing their political death certificates.

Bozell might be right about political death certificates, but if so, it will likely be because Republican voters might not understand that the supermajority component is not the most important issue in a BBA proposal.  First, Senate rules already supply a de facto supermajority requirement on most legislation with the filibuster.  That forces bills to get 60 votes in order to proceed to debate, and then 60 again to proceed to a floor vote.  That does not apply to appropriation bills, of course, and shouldn’t to judicial confirmations, but they do apply to everything else as long as the Senate keeps the filibuster in the rules — and they have no incentive at all to end it.

Besides, supermajority requirements in the Constitution only exist for critical issues such as amending the Constitution itself, election of a President in Congress in case of an Electoral College tie, impeachment of federal officers, and treaty ratifications.  There is no other supermajority requirement on domestic policy in the Constitution; clearly the framers considered simple majorities suitable for domestic policy.  That is a tradition that should be maintained.  If we cannot keep a majority from raising taxes, then either the tax increases contemplated have majority support in the nation or the nation will return a Congress that will roll such tax hikes back.

The most critical component of a BBA isn’t a supermajority restriction on tax increases, but a hard cap on spending linked to GDP.  The proposal pushed by Jim DeMint and conservatives included a limitation on federal spending, including spending on entitlement programs, to 20% of the previous year’s GDP (DeMint’s proposal also had a tax cap). I’ve seen other figures proposed, such as 18.5%, but 20% is closer to the average level of spending in Washington in the years preceding the 2007 Democratic majority in Congress.  If passed today, it would require about a 20% reduction in spending immediately in order to come into compliance.

Having a hard cap on spending level would greatly reduce the pressure for tax hikes.  Regardless of how much money came in, Congress would be unable to spend over the hard-cap amount, which means that tax hikes would become irrelevant.  Actually, they would become an albatross, since the only way to get more money to spend would be to drive up the nation’s GDP, and tax hikes generally damage economic growth.  In order to get more cash for any pet projects, Congress would be forced to implement pro-growth policies — and would also be forced to wait at least one year for the cap to be raised.

The real reason for a BBA is to put a limit on government spending.  Let’s focus on the real prize.