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How would a Biden administration use Trump’s unspent wall money?

Late Senator Everett Dirksen reportedly once said of federal spending, “A billion here, a billion there, and pretty soon you’re talking about real money.” So it is with the nearly $15 billion raked together since 2017 for President Trump’s border wall. Yet in four years, progress has been slow and much of the money appears to be unspent. This raises the question: If Vice President Biden prevails in November, what should his administration do with the unused funds?

A President Biden would have flexibility in making the decision because most of the funds were obtained through executive action rather than the appropriations process. The Trump administration reprogrammed $6.3 billion of Department of Defense counterdrug funds, $3.6 billion in military construction projects (MilCon) and $601 million from the Treasury Forfeiture Fund (TFF). Only $4.5 billion of the total — shy of one-third — was actually approved by Congress. Although state attorneys general have challenged the spending, the Supreme Court has allowed construction to proceed.

How much money is left? There’s reason to believe it’s quite a lot. Despite expediting construction, the Department of Homeland Security reports that only 300 miles have been completed so far, nearly all of which represent repairs to, or replacement of, existing structures. Mirroring the slow progress, numbers show that the Army Corps of Engineers has expended less than $3 billion on relevant DHS projects since 2017.

So, barring a spending spree, billions could still be available on Inauguration Day. At that point, a President Biden would have three options. 

Option 1 is to return all reprogrammed funds to their original purposes. Democrats in Congress would likely support this option, as it would show respect for their appropriations authority. The state attorneys general likewise would approve, since reversion of the funds is, in effect, one of the remedies they seek.

But this first option is also the most conventional and a Biden administration should not embrace it uncritically. There are two additional options which, although unorthodox, could yield political and practical advantages.

Option 2 is to redirect unspent TFF and DoD counterdrug funds to upgrade the ports of entry. If border security is the aim, this is the better way to achieve it; the majority of drug smuggling takes place at the U.S.’s ports of entry, not in the borderlands between them. And border hawks would be reassured by these investments in port security, even as a Biden administration rolls back other aspects of Trump’s hardline immigration policies.

Yet, under this option, a Biden administration would still revert the MilCon funds. This may be legally required if Biden rescinds Trump’s border emergency proclamation, and it would also be a boon to the service branches. According to a memo from Department of Defense Secretary Mark Esper, the projects currently deferred in favor of the wall include more than $2 billion in airfield upgrades, new command facilities, on-base schools for the children of service members and other much-needed enhancements, both at home and overseas.

Option 3 is the most inventive, but could pay the greatest dividends. A Biden administration could use unspent funds to improve U.S. coordination with Mexico in securing the border and fighting organized crime. In essence, the administration would redirect TFF and counterdrug funds in ways that allowed DoD and DHS to offset the costs of improving security along Mexico’s southern borders, thus mitigating migrant flows closer to their source in the Northern Triangle countries of El Salvador, Guatemala and Honduras. Those same funds could also offset the costs of deepening collaboration with Mexico’s interior counterdrug efforts, reducing the northward flow of narcotics and relieving pressure on drug enforcement authorities at U.S. ports of entry. 

To be sure, Options 2 and 3 could stir some controversy. Some might even claim that they would repeat an abuse of executive power that Trump pioneered. But a Biden administration could moot those critiques by simply coordinating with Congressional leadership and obtaining buy-in from the states. Regardless, Biden’s administration would need more than conventional solutions and old orthodoxies to remake the nation’s border security in the wake of Trump.

Of course, it is also possible that the Trump administration will rush to spend down all $15 billion on the border wall in the months to come, leaving the cabinets bare. In that case, a Biden administration, if there is one, will simply have to start where most administrations do: asking Congress for a billion here, and a billion there.

Timothy Perry is a law professor who frequently writes on matters of homeland security. He previously served as an assistant U.S. attorney along the southwest border in San Diego, during the Bush and Obama administrations.