While many in Washington believe that we don’t spend nearly enough money on our military, no one disputes that we are spending a lot. The central issue pertains to whether we are getting less than we used to for what we spend today, and whether our security is imperiled as a result.

In a recent commentary posted at the National Interest online, the Heritage Foundation’s Justin Johnson makes the case for spending more on the military. Americans, he says, “have every reason to be concerned about the state of the U.S. military.” But is more money the answer? The United States could, instead, seek to get more bang for its buck by reforming the way the Pentagon does business, and by revisiting the military’s roles and missions.

First, the facts. U.S. military spending today, as it is dictated by the bipartisan Budget Control Act (BCA), is comprised of the Pentagon’s base budget excluding the cost of recent wars. This spending is approaching historic highs. In inflation-adjusted dollars, U.S. taxpayers will spend more on the military in each of the next five years ($510 billion) than was spent, on average, during the Cold War ($460 billion). And, again, that spending gap doesn’t take into consideration today’s war costs.

Now, some will object that comparing inflation-adjusted military expenditures is insufficient. Johnson chose to focus instead on military spending as a share of GDP, the military’s share of total federal expenditures and the U.S. share of global military spending.

Military spending as a share of GDP has been declining for the past several decades, and falling as a share of total federal spending since 2008. It is projected that the interest on the national debt will eclipse military spending within the next ten years. And the United States, which once accounted for 48 percent of global military expenditures, now accounts for 38 percent. Still, Johnson does not dispute that America is spending more in absolute terms.

Why spending levels matter, meanwhile, is distinctly subjective. Citing a Heritage Foundation study, Johnson claims that calls to cut military spending are dangerous because the global threat level is “elevated,” and “America’s ability to defend itself and its interests” is “only ‘marginal.’ ”

Is that really so? Would any other country on the planet trade places with Uncle Sam today? Are Americans today less safe than those living during the Cold War? Or World War II?

To be sure, the U.S. military is indeed smaller today than it was six years ago, or during the Cold War. Consider it just in terms of the number of men and women serving on active duty. In 1952, at the height of the Korean War, active-duty end strength peaked at 3.6 million. During the Vietnam War, the number of active duty personnel reached 3.5 million. The high point in the post–Cold War era came in 2010, when active duty end strength peaked at 1.5 million, less than half the number in uniform at the time of those earlier wars. And yet total Pentagon spending was higher in 2010 than in either 1952 or 1968 — 35 percent higher than in 1952, and 32 percent higher than in 1968.

A similar story could be told with respect to ships at sea, or planes in the air. The platforms we are buying today are more costly than those fielded a generation ago. We spend more, and we get less.

Or do we? Is spending itself necessarily correlated with effectiveness? Does a larger budget for the Department of Education lead to better education for our kids? Does higher health care spending ensure that we will all live healthier lives?

We should ask similar questions with respect to the Pentagon’s budget. The military of my parents’ generation was comprised primarily of conscripts: men obligated by law to serve, often against their will. They were poorly paid and received minimal training because it would have been foolish to invest time and money in those who were unlikely to remain in uniform for more than a few years. They executed their missions, often heroically, and under harsh conditions. But they were, by and large, temporary soldiers, anxious to return to their civilian lives when the wars were over, or when their obligated term of service was up.

With no disrespect intended to the generations who fought in World War II, or Korea, or Vietnam, I would argue that today’s military is superior — truly the finest fighting force in our nation’s history — because it consists entirely of dedicated professionals who have volunteered to serve.

In light of this choice, taxpayers are willing to pay service members well, relative to their comparably skilled peers. The entire package of salary and benefits must be competitive with the private sector in order to attract and retain the very best talent. It’s about more than just pay, however. We are willing to invest heavily in training military personnel because such an investment is so widely believed to yield dividends.

So, yes, we spend a lot. But the cost effectiveness of our defense spending is debatable — a worthy debate, at that.

Notwithstanding Johnson’s efforts, then, it isn’t obvious that a more costly force is needed to preserve U.S. security and protect vital U.S. interests. That we are spending less as a share of GDP than at some points in U.S. history does not necessarily mean that we should spend more. It could also be true that we are spending less and getting more, or that we could safely get by with less. Once we get beyond the confusion over different ways to measure our spending, let’s examine what the U.S. military truly must do in order to keep Americans safe, and how much that will cost.