WASHINGTON — The overdose of Reagan nostalgia to which we’ve been subjected during the Republican presidential primaries is as understandable as it is misplaced. Understandable, because each party has its icons. Misplaced, because we have never really risen far from Reaganism at its most basic level, and there can be no nostalgia for a time that has not really passed.

The supply-side economic theory of granting enormous tax cuts to the wealthy in hopes that dribbles would “trickle down” to the rest was resurrected with President Bush’s tax cuts of 2001 and 2003. They are more tragic in their result than even President Reagan’s tax cuts were, as the Bush era has been marked by evidence that economic inequality is growing more and more extreme. After the terrorist attacks of 9/11, Bush started one necessary war in Afghanistan and a tragically misguided one in Iraq, two conflicts that many Americans believe are responsible for a run-up in defense spending for which future generations shall pay.

They are only partly right. Just as it did under Reagan, routine defense spending under Bush has been rising without restraint, gobbling an ever larger share of the federal budget and growing as a percentage of the nation’s economic output, according to a new study by the liberal-leaning Center on Budget and Policy Priorities. Excluding the costs of the wars in Afghanistan and Iraq, as well as expenditures for the global “war on terror,” spending for defense and related security programs has gone up 4.8 percent per year since 2001, after adjusting for inflation.

To understand the full measure of this number, analyst Richard Kogan compared it with spending growth in the big entitlement programs — Medicare, Medicaid and Social Security. These are the programs we are incessantly being told are ballooning so far out of control that they are “unsustainable” and somehow driving the nation toward bankruptcy. Kogan found that the three programs, averaged together, grew by only 3.8 percent per year since 2001. Even that figure includes spending that resulted from adding a prescription drug benefit to Medicare, the largest expansion of the health-insurance program since its inception more than four decades ago.

The numbers are even more skewed when defense spending is compared with the growth in domestic discretionary spending, that portion of the federal budget that pays for such necessities as law enforcement, highways, air traffic control and so forth. Kogan found that defense spending has grown 27 times as fast as discretionary domestic spending, when inflation and population growth are taken into account.

Quibbling with this or that way of parsing budget numbers is a political art form. But an overarching point of agreement between Republicans and Democrats, one that cannot be disputed, is that since the Democrats took over both houses of Congress, they have not even nicked the Pentagon. Indeed, Sen. Kent Conrad, D-N.D., chairman of the budget committee, boasted of this compliance in a floor speech delivered on Tuesday, as the chamber was deliberating this year’s budget resolution. Countering Republican claims that Democrats were shortchanging the troops, Conrad said: “We have the identical amount in our budget for defense and the war as the president had in his budget — identical, not a dime of difference.”

So there you have it. The Democrats’ political posture is that questioning Bush’s runaway defense spending is such a loser that they dare not risk it. Whether this allocation of scarce resources is actually in the public interest does not enter into it. This framework, carried to its logical conclusion, means that even if the wars in Afghanistan and Iraq were to end quickly — and no one is predicting that they will — there will be no “peace divided.”

Neither Barack Obama nor Hillary Clinton, the two remaining candidates for the Democratic presidential nomination, has pledged any significant reordering of budget priorities, except that both say they intend to scale back that portion of the Bush tax cuts that flows mostly to the wealthy. The Republican nominee, John McCain, harrumphs mostly about congressional “earmarks,” those for-my-district spending provisions that raise the public’s hackles but account for a pittance of federal spending. Eliminate every single earmark, and there would still be a huge budget deficit and an enormous imbalance in the way taxpayer resources are allocated between domestic and defense spending.

This is Reaganism at its worst, and we endure it now even without the comforting gloss of Reagan’s rosy demeanor.

Marie Cocco’s e-mail address is mariecocco(at)washpost.com.