July 19 (Bloomberg) -- Perhaps it’s a law of politics: For every political fantasy of Democrats there is an equal and opposite one from Republicans. Democrats have been pretending that the Constitution allows President Barack Obama to ignore the debt ceiling, so that he doesn’t have to compromise with Republicans in Congress. House Republicans are voting this week on their own dream: a constitutional amendment to enshrine their budget views and eliminate the need for compromise with Democrats, forever.

The slogan for this campaign is “cut, cap and balance.” The bill Republicans are promoting this week would condition any increase in the debt limit on immediate spending cuts, caps on future outlays and congressional passage of a balanced-budget amendment to the Constitution.

To increase the debt limit, two-thirds of Congress would have to vote for the amendment and thus send it to the states for ratification.

The amendment most Republicans have in mind is more stringent than previous versions on which Congress has voted. In addition to requiring revenue and spending to balance, it would require a two-thirds vote of Congress to raise taxes. It would also limit spending.

No Spending Increases

Over the past few decades federal revenue has, on average, amounted to 18 percent of gross domestic product. Spending has averaged 20 percent but is now at 24 percent. The amendment would require that spending stay at or below 18 percent (with exceptions when war has been declared or a supermajority of Congress has voted to waive the spending limit).

So spending would not be allowed to increase to accommodate the growing number of retirees on government assistance, or the rising cost of health care. Instead spending would be cut so that taxes could stay at their historical levels.

Thirty-seven Republicans in the House and 12 in the Senate have taken a pledge not to support a debt-limit increase without congressional passage of the amendment. Mitt Romney and Tim Pawlenty are among the Republican presidential candidates who have also taken it. Many conservative activist groups, such as the Club for Growth and FreedomWorks, are insisting on cut, cap and balance.

As a conservative I share the goal of a government that spends no more than 18 percent of GDP, and ideally spends less. But is it really wise to make putting that goal into the Constitution a condition of raising the debt ceiling?

The cut, cap and balance campaign assumes that Tea Party zeal, the popularity of balanced budgets and Obama’s need to increase the debt limit can be leveraged to win a policy outcome well to the right of anything that the all-Republican government of a few years ago ever achieved.

Implausible Assumptions

Either that campaign assumes that hitting the debt limit won’t hurt, or it makes several other implausible assumptions.

It assumes that although Obama is balking at a deal that includes steep spending cuts and no tax increases, he can be made to accept constitutionalizing such a deal (he has vowed not to). It assumes that even though state governments increasingly depend on federal deficit spending to keep their own budgets in balance, 38 of them are likely to ratify a government-slashing amendment.

And it assumes that Congress can find a two-thirds majority to pass the amendment in time.

“A Good Compromise”

Representative Mick Mulvaney, a freshman Republican from South Carolina who is a leading supporter of the amendment, said in an interview that if “the president wants this debt-ceiling increase, he’s going to help us get the votes.” He argued that Obama should deliver 50 Democratic votes in the House and 20 to 30 in the Senate. “That’s a good compromise for both sides.”

Does the congressman think that 50 Republicans would vote for a constitutional amendment that contradicts everything they stand for if President Romney asked them to?

What a congressman who pledges to increase the debt limit only if a spending-limit amendment passes is really saying is that he opposes increasing the debt limit. Because there is no way that two-thirds of Congress is going to pass this amendment now, or ever.

It’s also unclear how the amendment would be enforced if it did pass. Presumably most conservatives would not want the federal courts to step in to decide how much to spend on defense. Mulvaney is counting on a sense of honor and shame: “I think Congress would be hard-pressed to sidestep a balanced-budget amendment. It’s right there written out.”

Lack of Restraint

Well maybe. But it’s worth looking at a recent, low-profile vote the House took to restore $6 million that had been cut from a program to help rural people get broadband Internet service. Unprecedented deficits didn’t make the 90 Republicans and 131 Democrats who voted yes think twice, or try to find some way to pay for the cost. They didn’t seem worried about a public backlash against them for overspending.

Among those 90 Republicans were Tea Party favorites Kristi Noem of South Dakota, Steve King (Iowa), Jim Jordan (Ohio), Mike Pompeo (Kansas), Raul Labrador (Idaho) -- oh, and Mulvaney as well. One-third of the House pledge-takers voted for the legislation.

It is, of course, a small sum in comparison to the whole federal budget. But it does raise some questions: If Congress lacks the will to impose this tiny amount of spending restraint, is it really going to cut trillions from the budget? If the leading supporters of a balanced-budget amendment don’t have the will to restrain themselves, how do they expect to succeed?

(Ramesh Ponnuru is a senior editor at National Review and a Bloomberg View columnist. The opinions expressed are his own.)

Read more Bloomberg View columns.

To contact the author of this column: Ramesh Ponnuru at rponnuru@bloomberg.net.

To contact the editor responsible for this column: Timothy Lavin at tlavin1@bloomberg.net.