(Bloomberg Opinion) -- As the campaign for the Democratic presidential nomination intensifies, so will the pressure on the U.S. defense budget. The Pentagon recently submitted its budget request for fiscal year 2020, which comes in at an impressive $750 billion. Yet Democratic senators and presidential aspirants such as Elizabeth Warren and Bernie Sanders had already been criticizing existing levels of defense spending, arguing that a $700 billion-plus defense budget undermines efforts to promote progressive change at home.

This argument is a staple of progressive rhetoric, and you’ll hear it often in primary season. It also happens to get things backward. Progressives should learn to love, or at least tolerate, high levels of military spending precisely because it tends to advance a key progressive goal: Improving the economic fortunes of the middle class. 

The progressive left has long criticized high defense spending on numerous grounds. They often argue that it is unnecessary, because the U.S. is so inherently safe and its advantages are so overwhelming. They say the money is even counterproductive, because it tempts the U.S. to engage in military adventures abroad.

Their core argument, however, is that large military outlays are incompatible with progressive domestic priorities. Pentagon spending rewards fat-cat defense firms rather than working- and middle-class individuals, this argument goes, and it sucks away money that could be spent on education, creating clean jobs and other progressive policies. As Warren said in her speech at American University in November, it’s necessary to take a "sharp knife" to the Pentagon budget - to pare away programs that "merely line the pockets of defense contractors." 

Yet such comments are misguided in several respects. In one sense, they ignore that liberalism in the U.S. will be most secure in a world where liberalism is predominant - and that requires the liberal powers to maintain an overbalance of military might.

But even leaving aside the foreign policy argument, the progressive critique gets two things wrong. First, it misdiagnoses the source of America's budgetary woes and creates a misleading impression of how best to fund progressive programs. Defense spending accounted for roughly 15 percent of the federal budget in 2018, whereas entitlements (Social Security, Medicare, Medicaid) accounted for half. The greatest long-term threat to America's ability to invest in infrastructure, education and other progressive priorities is not the Pentagon. It is the combination of insufficient tax revenues (a problem progressives did not cause) and runaway entitlement spending that progressives have so far shown scant interest in containing. 

Second, and more important, the progressive critique misses the fact that military spending already serves progressive ends. Yes, defense spending benefits the executives who run major defense contractors, just as infrastructure spending benefits the executives of companies that build highways and airports and schools. But the Pentagon budget also serves as a huge jobs program and source of economic security for the middle class. This includes the roughly 2 million people who serve either on active duty or in the reserves and 730,000 civilian employees. The vast majority of them qualify as middle class and enjoy precisely the sort of health care and other benefits progressives seek to provide for the population as a whole. It also includes innumerable Americans whose economic livelihoods depend on a well-funded Pentagon – those who work for government contractors and the entire “defense industrial base.” 

New evidence on these points come from a study by the nonpartisan Carnegie Endowment for International Peace on whether American foreign policy serves the needs of the middle class. Using Ohio as a case study, the report concludes that defense spending "provides an economic lifeline for communities and households" across the state. Roughly 65,000 Ohioans work at military facilities, in tank factories, or in other defense-related jobs; communities such as Dayton and Lima could be devastated by significant contractions in military spending. Moreover, military service offers Ohioans - and people across the nation - access to myriad opportunities that might otherwise not be available.

"Across the state," the report notes, "a middle-class standard of living would be put out of reach for several thousand Ohioans if they could not count on the National Guard and Reserves as a way to contribute toward their educational expenses, acquire coveted training, earn a livable wage, provide healthcare, and add to their portfolio of retirement benefits."  

It is true that money spent on defense could theoretically be spent instead on other programs that might also benefit the middle class. But this may still be the wrong way to think about the issue. For one thing, defense spending produces massive positive spillovers in the form of national security and the ability to protect access to the global commons - critical to promoting U.S. trade and improving living standards at home. For another, defense spending is an easier political sell than many alternative programs - it is one of the few government employment schemes that Republicans consistently favor. "Arguably, defense spending enjoys more bipartisan political backing and potential for growth than any other source of federal funding to support national industries and middle-class livelihoods, education, training, healthcare, and retirement," the Carnegie report states. 

None of this means that this particular budget request should be considered sacred. The Pentagon’s proposal contains some badly needed investments in high-end capabilities that will be crucial to competing with China and Russia. Unfortunately, it also perpetuates the budget gimmick of shoving money into the so-called warfighting fund as a way of getting around the lingering spending caps imposed by the Budget Control Act of 2011. Worse still, it includes several billion dollars of border-wall funding that is effectively being diverted from authentic military purposes.

In exercising oversight of the defense budget, however, progressives should not lose sight of the fact that a well-funded Pentagon actually supports key parts of their domestic agenda. Making the American middle class stronger and more secure is one of the great challenges of our time, and progressives are right to focus on it. But taking a knife to defense spending is the wrong solution.

To contact the author of this story: Hal Brands at Hal.Brands@jhu.edu

To contact the editor responsible for this story: Tobin Harshaw at tharshaw@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Hal Brands is a Bloomberg Opinion columnist, the Henry Kissinger Distinguished Professor at Johns Hopkins University’s School of Advanced International Studies, and senior fellow at the Center for Strategic and Budgetary Assessments. Most recently, he is the co-author of "The Lessons of Tragedy: Statecraft and World Order."

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