Despite years of increasing defense spending, the U.S. armed services all insist they need more money. Many politicians and members of the public meanwhile insist the United States spends too much money on its military and should shift resources to other, more urgent needs.

The gap between the military on one side and, on the other, advocates of lower levels of defense spending highlights a vexing question. What does the United States get for its world-leading military budgets? And how much defense spending is too much?

Congress approved, and Pres. Donald Trump signed, a $718-billion budget for the Defense Department for 2020, marking the fifth year in a row of steady growth in defense spending that began under Pres. Barack Obama in 2016.

The United States by far is the biggest military-spender in the world, doling out roughly triple what China does annually for its own armed forces, not adjusting for the relative weakness of the Chinese economy. Russia spends only around a tenth what the United States does.

Despite this, the U.S. Army, Air Force and Navy all have declared they need more cash. “The United States Air Force is too small for the missions that the nation is expecting of it,” Heather Wilson, Trump’s air force secretary from 2017 to 2019, said early in her tenure.

“We’re going to need more money,” Acting Army Secretary Ryan McCarthy said in August 2019. Trump more than any previous president relies on temporary, “acting” agency heads in order to avoid the Senate approval process for permanent leaders.

Acting Navy Secretary Thomas Modly, who is under pressure to expand the front-line fleet from 290 to 355 ships, echoed McCarthy’s sentiment. “If you are growing the force by 25 to 30 percent, that includes people that have to man them,” Modly told Defense News in January 2020. “It requires maintenance. It requires operational costs. And you can’t do that if your top line is basically flat.”

Many critics disagree that that defense spending is “basically flat” and that any military branch is “too small.” Noting that many of America’s European allies spend just two percent of their gross domestic product on their armed forces, compared to the 3.5-percent that the United States spends, The Washington Post in late 2018 mulled some of the things the country could invest in if it reduced the military’s share of the budget to European proportions.

“Depending on which expert you ask, the chronic social ills the United States could go a long way toward addressing with an extra $3 trillion per decade include: homelessness, child poverty, college tuition costs, the national student debt burden, a lack of affordable child care and long-term health care for the elderly,” the Post explained. “It could also accomplish several key goals of the president, or go a long way to help balancing U.S. books.”

But Michael O’Hanlon, a military expert at The Brookings Institution in Washington, D.C., cautioned against what he called “badly oversimplified” proposals to increase or decrease spending.

“For example, many who wish to defend the magnitude of Pentagon spending often point out that in recent decades its share of the nation’s economy is modest by historical standards,” O’Hanlon wrote. As recently as the 1960s, the Defense Department budget accounted for nine percent of GDP. “Seen in this light, current levels seem moderate.”

“By contrast, those who criticize the Pentagon budget often note that it constitutes more than one-third of all global military spending, and three times that of the number-two global military power, China,” O’Hanlon added. “Or they note that estimated 2020 national security discretionary spending of more than $700 billion will exceed the Cold War inflation-adjusted spending average of around $515 billion, expressed in 2020 dollars.”

“The U.S. defense budget is and will remain large relative to budgets of other countries, other federal agencies, and even other periods in American history. Yet at the same time it is modest as a fraction of the nation’s economy, at least in comparison with the Cold War era.”

“The challenge for those who seek to make sense of the defense budget is to look more closely at how defense dollars are spent,” O’Hanlon concluded. “Only then can we decide if the budget is excessive or insufficient.”

BLOCKQUOTE

The challenge is identifying missions that are not needed, on the one hand, or under-resourced on the other; weapons that are too pricey or redundant versus those that may be imperative and even neglected under current plans; defense business practices that may be inefficient; and so forth.

That is a complicated process. So beware of simple statements about the defense budget.  Depending on who is doing the talking, one could imagine an American presidential candidate proposing anything from a $600 billion a year defense budget for 2021 and beyond to something closer to $800 billion.

Even by Washington and overall U.S. standards, that potential $200 billion discrepancy is real money—and translates into big differences in overall military capability.

David Axe serves as Defense Editor of the National Interest. He is the author of the graphic novels  War Fix, War Is Boring and Machete Squad.