If Washington politics are increasingly characterized by division and dysfunction, the National Defense Authorization Act (NDAA) exists as one of the last remnants of bipartisanship and good governance. For over half a century now, Congress has passed an NDAA every year.

In recent years, the Obama Administration has threatened to veto the NDAA but ultimately has signed each bill into law. It was no surprise, then, that the president issued another veto threat for the NDAA currently under consideration in Congress. This year, however, the tenor is different, as opposition to the NDAA from the president and leading Democrats has reached a fever pitch. Democratic Senators even considered filibustering the bill, though it is likely to pass the Senate today with bipartisan support.

President Obama’s NDAA veto threats have typically come with numerous justifications, but the administration’s strongest objections have been two-fold: restrictions regarding detainees at Guantanamo Bay and blocking funds for a Base Realignment and Closure (BRAC).

For the last three years, the veto threat came after House Republicans passed their version of the NDAA. Before this year, when Democrats were in control of the Senate, perhaps the administration hoped a veto threat may be effective in stripping the contentious Guantanamo and BRAC provisions during the conference process. Each year, however, those provisions remained in the final NDAA, and the president nevertheless signed the bills into law.

This year, with Republicans in control of the Senate, the administration might have more reason to believe the contentious provisions from the House bill would make it into the final bill. The Senate Armed Services Committee markup, however, includes a bit of a compromise on Guantanamo from Chairman John McCain. And a bipartisan amendment sponsored by Chairman McCain and Senator Dianne Feinstein to reaffirm the prohibition on torture was adopted on the Senate floor this week. The BRAC language is likely to survive a conference process again, as it is in both the House and Senate versions of the bill.

With similar BRAC provisions and the potential of a Guantanamo policy closer to the administration’s position, this year’s NDAA would be likely to survive a presidential veto threat again—except for one even more contentious matter: how the bill actually authorizes funding for the Department of Defense (DOD).

The amplified saber-rattling from the administration in recent months comes down to opposition to Congress’s use of emergency war funding to boost Pentagon spending above the post-sequestration cap that imposes devastating cuts to the military budget. President Obama and other Democratic leaders say they will only approve increased funding for defense if it is accompanied by higher domestic spending as well.

This position is misguided. The NDAA is not a spending bill. Rather, it is a defense policy bill—among other elements, it establishes end strengths for the armed services, prioritizes weapons systems procurements, and sets compensation levels for servicemembers. This year, both the House and Senate versions of the bill include reform proposals for the Pentagon’s acquisition system and military retirement.

The NDAA does not, however, fund the activities of the DOD. It sets forth the nation’s defense policies and establishes the levels of funds needed to carry out those policies. The actual funding is provided in appropriations acts that follow authorization bills such as the NDAA. Indeed, owing to some changes effecting mandatory spending, the NDAA actually reduces funding on defense-related activities by nearly $5 billion.

Further, vetoing the NDAA would fail to achieve the administration’s goal of stopping a defense spending increase without a domestic sequester fix. A veto would kill the policies in the NDAA, but the appropriations process could proceed nonetheless. In fact, with the notable exception of defense, Congress regularly passes unauthorized appropriations bills.

Threatening to veto the NDAA is picking the wrong fight. Holding the military’s budget hostage for the president’s domestic spending priorities is bad policy and bad politics. Both sides agree that using war funding to circumvent the sequestration cap on defense is an imperfect solution. Not sending extra funds to the Pentagon at all, however, would have devastating consequences.

Successive years of cuts to the defense budget have put our military on the verge of a catastrophe. Sacrificing the defense budget for a domestic agenda sends the wrong message to the men and women in uniform protecting this nation in an increasingly dangerous world.