Sen. Elizabeth Warren’s (D-Mass.) long-awaited plan to pay for her Medicare-for-all proposal will be justly attacked for its unrealistic assumptions regarding how to cut health-care costs and raise new revenue. Even more seriously, however, her plan includes an element that shows she approaches national security issues without sufficient care or thought.

That element is her proposal to eliminate spending on the Overseas Contingency Operations fund. This fund, appropriated each year by Congress, was initially used to pay for the Iraq War. In subsequent years, it has become the vehicle to pay for U.S. military operations in the war on terrorism and for ongoing military spending in excess of budget caps on defense spending. Since major military activities in Afghanistan ended earlier this decade, contingency operations funding has ranged from $62 billion to $92 billion a year, according to the Congressional Budget Office. Citing figures from the fiscal 2019 “People’s Budget” proposed by the Congressional Progressive Caucus, Warren says she thinks she can obtain $798 billion over 10 years for her health plan by eliminating the fund.

Doing this, however, would place severe strains on the United States’ ability to conduct responsible foreign policy and maintain a credible global military posture. To start, eliminating the fund would either require us to withdraw our forces without first obtaining a reasonable peace settlement with the Taliban, the Islamic State and Syria, or it would require further cuts to the regular defense budget to offset ongoing expenditures on those operations while deals are being negotiated. The first idea has been widely condemned by foreign policy experts in both parties; the latter would require reducing the size or modernization of the U.S. military.

These are important decisions that have long-range consequences for our security and our relations with our allies. They deserve extensive analysis and consideration in their own right. By blithely using this money to pay for her health-care plan without a serious discussion of these considerations and trade-offs, Warren shows disdain for and lack of understanding of foreign policy intricacies.

It’s simply not enough to say, as she does in her plan, that some military spending programs “merely line the pockets of defense contractors.” By setting an implicit ironclad goal of cutting the overall defense budget by 10 percent within one year of taking office, Warren doesn’t force the Defense Department to “prioritize or live within its means.” She forces it to rapidly reduce military personnel, deployments and weapons procurements to meet her own priority.

That means an immediate cut of $68.8 billion, roughly 10 percent of all discretionary defense spending, potentially taken exclusively from non-war on terrorism expenses. Personnel costs alone take up nearly a third of the military budget, so meeting this target would probably require extensive layoffs of civilian and on-duty employees. It could also require cancellation of or changes to existing military weapons contracts. It could force reductions in forces deployed overseas or push the United States to force its allies to pay more for their deployment in those host countries. Any one of these changes would be highly contentious. Doing all of them at once, under an artificial deadline adopted for non-defense reasons, would be simply irresponsible.

Defense spending would probably have to increase, not decrease, in coming years. China’s and Russia’s militaries are growing, while ours is at best staying about the same size. To use just one measure of this, by the 2030s, Russia and China could field as many as eight aircraft carriers, up from one in 2001. The United States, on the other hand, is projected to field the same 11 carriers it has now. That’s down from the 16 it possessed when the Berlin Wall fell in 1989. That’s not going to work, at least if we care about credibly maintaining our global alliance structure.

Trump’s conduct of foreign policy often scares serious foreign policy thinkers. Warren’s cavalier treatment of U.S. security needs, however, should scare them as much — or more.

Read more: