House Speaker Nancy Pelosi is urging colleagues on both sides of the aisle to support a resolution terminating President Donald Trump’s national emergency declaration on border security. The bill, scheduled to be voted on within 16 days, will almost certainly pass, and then go to the Senate. There, it is legally required to receive a vote within another 18 days (under 50 USC § 1622). Only four Republicans need to break ranks and vote with Democrats for the resolution to pass.

A growing number of GOP senators have already expressed reservations about the President’s end run around Congress and the use of emergency authority for border security. But the vote on the resolution may ultimately be less about principled constitutional objections and more about concern over the President taking essential military construction dollars from senators whose states rely heavily on those appropriations. A look at where the money for a border wall might actually come from is instructive.

President Trump’s national emergency declaration lays out three sources for the funding he intends to use for the border wall. The first two sources — $600 million from a Treasury asset forfeiture fund and $2.5 billion from Department of Defense (DOD) counter-narcotics accounts — are not contingent on the emergency declaration. The third source of money, $3.6 billion from military construction accounts, is the one that draws on the emergency declaration authority and requires the concurrent deployment of U.S. military forces to the border to open up the account.

Legal experts have noted that military construction funds might not be available to build the wall: as former Principal Deputy General Counsel of DOD Bob Taylor explained at Just Security, it is “not enough that there be a ‘national emergency;’ that national emergency must be one that ‘requires use of the armed forces,” and the military construction projects that may be authorized are only ones ‘necessary to support such use of the armed forces’ (see 10 U.S.C. § 2808). Others have noted that, given long lead times to begin construction projects and the ongoing court challenges, the national emergency may be long over, whether invalidated by a court or because President Trump loses his reelection campaign and his successor terminates or declines to renew the emergency, by the time the government exhausts the asset forfeiture and counter-narcotics funds and begins drawing on military construction accounts.

The Politics of Military Construction

But before we get to any of that, the President’s ability to survive the uproar he has touched off will rely on his convincing enough Senate Republicans to join Mitch McConnell in backing his plan and thwarting the Democratic House’s resolution. And that will likely be heavily shaped by the politics of military construction.

One of the oddities of congressional committee structure is that more than 98 percent of DOD’s nearly $700 billion budget, along with the nearly $60 billion Intelligence Community budget, is handled by one appropriations subcommittee, and the small military construction budget ($11.2 billion in 2019) is handled by another subcommittee, which also appropriates funds for the Department of Veterans Affairs. The authorizing side is somewhat less confusing, with the Armed Services Readiness subcommittees in each chamber handling military construction and a range of other accounts.

Whatever the origins of the current appropriations and authorizations structures, the reality is that military construction often translates into local jobs and local spending. And with earmarks having been banned in 2011 after years of profligate misuse, military construction is one place where members of Congress can pull strings to bring money home. Indeed, winning over the eight Senate GOP appropriators and six authorizers responsible for military construction may be the key to President Trump’s gambit.

One look at the authorizations, appropriations, and budget requests underpinning military construction emphasizes just how heavily Congress and DOD micromanage this basket of spending. The DOD budget justification for military construction alone runs nearly 400 pages, laying out the details of specific programs and providing state- and country-specific breakdowns of spending. All new major projects also are specifically authorized in the annual National Defense Authorization Act, and the annual appropriations acts are accompanied by dozens of pages of report language stipulating how the money is to be spent and specifying line item adjustments to the Department’s request.

To be sure, the process is much tighter than it once was. The freewheeling earmarking that reigned in the decades after the founding of the military construction appropriations subcommittee during the 1950s Cold War buildup has been checked, most notably by reforms introduced by the late Senator John McCain in 1995.

But the careful process of requesting, authorizing, and appropriating military construction funds in some ways makes the President’s push to carve out funds even more complicated. To procure his desired $3.6 billion, he will have to cut through a tangle of carefully negotiated deals that were based on a mix of military requirements and local interests. Compounding this is the fact that, while military construction funds generally are available for five years once appropriated, the budget has been on a downward trajectory over the past decade. So freeing up $3.6 billion, even by drawing on funds appropriated prior to the current year, is no easy task.

That’s the complexity of the issue. In addition, the cold, hard politics means the President will have to convince the 14 senators responsible for military construction authorizations and appropriations to stick with him. Acting Secretary of Defense Patrick Shanahan will have to do his part as well, since the law requires him to notify Congress in advance of any emergency military construction spending.

Where Do They Stand?

Trump has already faced significant pushback from several GOP senators, many of whom have significant military construction spending in their states. Susan Collins of Maine just announced that she will back the resolution opposing the emergency declaration. The moderate senator has regularly expressed concern over the President’s actions but rarely taken action. In this case however, $161.3 million of 2019 funding alone is on the line, including much-needed enhancements to the Naval shipyard in Kittery, Maine. (Most major military installations will see several different projects funded in multiple years of appropriations, meaning that the total impact of military construction on any given region often ends up many times greater than reflected in a single year’s appropriations.)

Lisa Murkowski of Alaska and Marco Rubio of Florida have expressed their concerns about the declaration. Murkowski’s Alaska colleague Dan Sullivan, as well as Martha McSally of Arizona and Deb Fischer of Nebraska have all said they are studying the issue further. For Murkowski and Sullivan, the stakes are particularly high; Alaska is due to receive $286.8 million in military construction spending for 2019, including massive outlays for an Air Force base near Fairbanks, as well as missile defense installations. Both in real terms and on a per capita basis, Alaska has consistently been one of the top states in military construction expenditures over the past several years.

Rubio’s dilemma is only slightly less complicated; Florida’s total haul from the 2019 appropriations, $177.4 million, is smaller than Alaska’s share, and Florida has a larger population and more diverse economy, but $111.5 million of it is programmed for the Mayport naval base, one of the East Coast aircraft carrier bases, home of the Navy’s Fourth Fleet, and a major driver of economic activity in the Jacksonville area.

The appropriations subcommittee chairman, John Boozman (AR), along with Marsha Blackburn (TN), Joni Ernst (IA), and David Perdue (GA) have yet to weigh in on the issue at all. For Perdue, the dilemma is particularly stark. He has been a staunch supporter of the President, and his brother serves as Trump’s Secretary of Agriculture, but Georgia is a major military state due to receive $112.6 million for military construction in 2019, both for the Army’s Fort Benning, the service’s fifth largest U.S. base, and for Fort Gordon, the home of the Army’s cyber center of excellence.

All told, out of all 14 senators with responsibility for military construction appropriations and authorizations, only four — Shelley Moore Capito (WV), John Hoeven (ND), Steve Daines (MT), and Mitch McConnell (KY) — have signaled their support for the President’s declaration. But Montana is due to receive only $15 million for military construction in 2019 and West Virginia has no appropriations for the year, making Daines and Capito’s decisions easier. Hoeven is the only one of the 14 with significant funding on the line who has strongly backed Trump.

A Trio of Bad Options for Senators

At this point, for the senators still studying the issue or who have yet to comment, they basically have three options, all of them bad. First, they can challenge President Trump in an effort to defend their military construction projects and face potential backlash at home, since most of the undecided senators come from deep red states with strong support for President Trump. But this is a significant challenge because those same states also have large swaths of military voters who want to see their installations appropriately funded.

Another option is to support President Trump’s declaration but negotiate with the administration to make sure that preferred military construction projects are protected and not raided to support the wall. Indeed, this seems to be the approach that some in the House have already taken, with House Military Construction subcommittee ranking member John Carter indicating that he supports the President but that the declaration definitely will not affect the Mayport naval base. No doubt the administration’s current legislative wrangling involves cutting these kinds of deals and winning over skeptical Republicans.

A final option is that senators can support Trump and roll the dice that the courts will overturn the declaration, President Trump will be voted out of office, or another Congress will appropriate funds for the wall before the national emergency hits military construction accounts. This path, of course, is full of uncertainty.

Any way you cut it, it’s a tough vote for GOP senators. As long has been the case in Washington, far preceding the Trump era, the outcome may hinge less on high-minded constitutional principles or a desire to protect the rule of law and more on delivering for the folks back home.

[Editor’s note: readers may also be interested in former Under Secretary of Defense Comptroller/Chief Financial Officer at the Department of Defense Michael McCord’s “Power Struggle Over the Wall: Presidential Emergency Powers vs. Congressional Power of the Purse,” Just Security, February 21, 2019.]

IMAGE: Sen. Lisa Murkowski (R-AK) (2nd L) delivers remarks during an event to celebrate Congress passing the Tax Cuts and Jobs Act with (L-R) President Donald Trump, Rep. Don Young (R-AK), Sen. Dan Sullivan (R-AK). (Photo by Chip Somodevilla/Getty Images)