Just about the only thing the president and his detractors agree on regarding his 2007 budget is that it’s austere – but they’re both wrong. Don’t believe the spin. The truth is, President Bush is proposing significant spending increases, and Congress is almost certain to outspend his requests by a wide margin. Runaway spending is scheduled to continue unabated unless the president makes congressional Republicans start taking spending restraint seriously. The easiest way to do that would be to veto a bloated appropriations bill.

Last year, Mr. Bush proposed a 2006 budget that included $2.57 trillion in total government spending, a 3.9% increase from 2005 spending levels. Congress upped the ante by appropriating $100 billion more than the president requested, boosting overall spending at 8%, more than double what Mr. Bush requested. The president signed all of those appropriations bills into law. It gets worse. In his new 2007 budget, Mr. Bush requested even higher spending for 2006 – specifically, he wants to spend another $40 billion above what Congress appropriated, bringing 2006 spending in a shocking 9.6% higher than 2005.

This is hardly unique to 2006, but rather has been a consistent pattern throughout the first five Bush budgets. Those five budgets have requested average spending increases of 4.6%, but the actual results over the past five years have been an average growth of nearly double that – 7.8%.

The pattern is not explained by faster than expected growth in military and entitlement spending alone, because the numbers are exactly the same on the nondefense discretionary side – 4.6% annual growth requested, and 7.8% growth delivered. In 2006, nondefense discretionary spending, under the new Bush budget, will grow an extra $22 billion above what the president requested for this year in last year’s budget. That’s 4.7% higher than the original budget request, an even bigger jump than the average overshoot of 3.1% in Bush’s first five budget years.

The spending numbers for 2007 may look like restraint, but they’re misleading for two reasons: First, the annual growth numbers are built on that sky-high 9.6% increase in 2006; second, there is no indication as yet to believe that final 2007 spending won’t grow by several percentage points more than this initial request.

The bottom line is that Mr. Bush has played a large part in the Washington spending epidemic. The U.S. Constitution gives the president an immensely powerful device for checking the congressional budget process: the veto power.

Mr. Bush asked Congress to restore the line-item veto in his state of the union, but if he’s serious about stopping runaway federal spending, he needs to familiarize himself with an old-fashioned, regular veto, a potent tool for controlling spending that, as yet, he has never seen fit to use.

The veto is a blunt but effective instrument for blocking unnecessary spending. Many successful presidents have made liberal use of the veto over the years. Yet in over five years as president, Mr. Bush has not vetoed a single piece of legislation. That’s indisputable evidence that if Congress is unwilling to hold the line on spending, so is Mr. Bush.

Mr. Bush’s unwillingness to use the veto is odd given the successful veto record of previous presidents.

Both Ronald Reagan and Bill Clinton used the veto effectively to advance their agendas. Vetoes not only block the most egregious pieces of legislation, but more importantly they create a credible threat that gives the president leverage to influence other legislation and enforce fiscal discipline. Even in the worst case scenario of an override, and given the polarization of Congress it seems unlikely two-thirds could agree on anything controversial, Mr. Bush would still send a strong signal that his cooperation cannot be taken for granted. Congress would take notice and perhaps become more serious about spending.

Ultimately, it falls to the president to reverse Congress’s natural tendency toward profligate domestic discretionary spending by wielding his veto pen as a spending-slaying sword.

The key to continued American prosperity is not spending more federal money and driving the national debt into the stratosphere. Many presidents have tried that strategy, and it has yielded woeful results. The road to prosperity is paved with aggressive, rapid, spending cuts, coupled with the successful tax policies of recent years, both locked in for the long term.

Mr. Kerpen is policy director for the Free Enterprise Fund.