Secretary of Defense Jim Mattis on Capitol Hill on Oct. 3. (Aaron P. Bernstein/Reuters)

The Pentagon and the welfare state have been locked in brutal combat for decades, and the Pentagon has gotten clobbered. Protecting the country was once the first obligation of government. No more. Welfare programs — Social Security, Medicare, food stamps and other benefits — dwarf defense spending. As a result, we have become more vulnerable.

Here is the assessment of Mackenzie Eaglen, a defense specialist at the right-leaning American Enterprise Institute:

“The United States now fields a military that could not meet even the requirements of a benign Clinton-era world. The services have watched their relative overmatch and capacity decline in almost every domain of warfare . . . for nearly two decades. As rival nation-states have accelerated their force development, the Department of Defense has stalled out, creating a dangerous window of relative military advantage for potential foes. . . . While the United States continues to field the best military personnel in the world, policy makers have asked them to do too much with too little for too long.”

Politically, the vaunted military-industrial complex has been no match for the welfare state's personal handouts. There has been a historic transformation. In the 1950s and 1960s, defense spending often accounted for half of the federal budget and equaled 8 to 10 percent of gross domestic product (the economy). In 2016, defense spending was 3 percent of GDP and 15 percent of the federal budget, according to the Office of Management and Budget. Meanwhile, welfare programs — called "human resources" by the OMB — accounted for 15 percent of GDP and 73 percent of federal spending.

(A note for policy wonks: Some military spending occurs outside the Defense Department, but including this spending would not much change trends or conclusions.)

There are many telltale signs that defense spending, though now exceeding $600 billion annually, is being squeezed. A new study by Todd Harrison and Seamus Daniels of the Center for Strategic & International Studies reports the following:

— “For FY [fiscal year] 2015, the Army’s active duty end strength reached the lowest level since the end of World War II.”

— “The Army has noted in congressional testimony that two-thirds of its Brigade Combat Teams (BCTs) are not at an acceptable level of readiness because of personnel shortages, maintenance backlogs and insufficient training.”

— “From its peak in FY 1987 to the trough in FY 2015, the Navy’s ship count fell by more than half.”

— “The total aircraft inventory of the Air Force declined by 44 percent from its peak in FY 1986 to FY 2016.”

Sizable increases in defense spending seem warranted to compensate for past underfunding and to confront new challenges. China and Russia loom as potential adversaries; North Korea could become a global menace; the Middle East remains a cauldron of conflict; global terrorism survives; and new forms of warfare — cyberattacks, drones and space-based conflict — demand new responses.

Proposals abound. The plan of AEI’s Eaglen would, among other things, increase the Army’s number of active-duty soldiers from 476,000 to 519,000 by 2025; raise the number of Navy ships from 275 to 339 by 2025; expand the Air Force’s inventory of planes to 6,391 by 2022, up from 5,465; and accelerate research and procurement.

John McCain (R-Ariz.) and Mac Thornberry (R-Tex.) — the chairmen of the Senate and House armed services committees, respectively — have endorsed a similar proposal. So has the Trump administration, though with less detail. The problem is not policy; it’s politics.

Eaglen's plan would cost $672 billion more than existing law over the next five years. Will Congress vote to spend that money? If so, will it be financed through higher taxes (seems dubious, given Republicans' misplaced zest for tax cuts); reductions in other government programs (also dubious — if cuts were popular, they'd already have been adopted); or borrowing (the easiest alternative, but embarrassing)? Present congressional budget negotiations for fiscal 2018 focus on a smaller increase in defense outlays.

Defense spending is increasingly a political orphan. Republicans are wedded to tax cuts. Democrats are addicted to welfare spending, mislabeled as “entitlements.”

What these political preferences have in common is that they provide immediate political gratification for large constituencies: lower taxes or higher benefits. By contrast, defense spending confers smaller benefits on smaller constituencies, mainly workers at military bases and government contractors.

In the competition for scarce public funds, the military-industrial complex is at a distinct disadvantage with the welfare state, an essential and permanent part of our social fabric. No one is going to dismantle it. But the favoritism toward the welfare state weakens the military. It is time to recognize and rectify this bias because it poses a fundamental threat to our collective well-being.

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