The House of Representatives easily passed its version of the 2019 National Defense Authorization Act (NDAA) on Thursday, sending the Senate a strongly bipartisan bill that calls for the National Nuclear Security Administration to begin work on a low-yield, submarine-launched ballistic-missile warhead.

The same day, the Senate Appropriations Committee also overwhelmingly approved funding for the new warhead, which will be a modified version of the W76 warhead that currently tips Trident II-D5 missiles carried aboard Ohio-class submarines.

Both versions of next year’s NDAA authorize $65 million for the weapon, as do 2019 Department of Energy spending bills that have now cleared the appropriations committees in both chambers.

The House’s 2019 NDAA, an annual military policy bill that sets spending limits for appropriators, cleared the lower chamber 351-66. All but seven of the “no” votes were Democrats.

Rep. Adam Smith (D-Wash.), who this week made an impassioned floor speech against the low-yield warhead, called for in February by the Trump administration’s Nuclear Posture Review, ultimately voted in favor of the bill.

The Senate Armed Services Committee on Thursday voted 25-2 to advance its version of the policy bill. The full text of the Senate committee’s NDAA had also not been published at deadline, though a summary had.

In Senate appropriations markups this week, Sen. Dianne Feinstein (D-Calif.), who strongly opposes the weapon, says it will cost $125 million over two years to complete the low-yield W76 warhead.

Overall, the House’s version of the 2019 NDAA recommends $15.3 billion for the NNSA: about 4.5 percent more than the 2018 appropriation and about 1.5 percent more than the White House requested for 2019. The bill calls for a series of reports on crucial NNSA defense programs, such as the B83 gravity bomb the administration wants to keep active beyond its previously planned end of service next decade. 

The House NDAA does not recommend the NNSA plan to split production of plutonium pits — fissile nuclear-warhead cores — between the Los Alamos National Laboratory in New Mexico and the Savannah River Site in South Carolina. The agency on May 10 said it wanted to repurpose the Mixed Oxide Fuel Fabrication Facility, being built at Savananh River to turn 34 metric tons of weapon-grade plutonium into commercial reactor fuel, into a pit plant.

The summary of the Senate NDAA was silent about the two-pronged pit approach, or the NNSA’s plan to cancel the existing nonproliferation mission of the Mixed Oxide Fuel Fabrication Facility. However, Sen. Lindsey Graham (R-S.C.), who strongly opposes canceling that mission, said in a Senate Appropriations Committee markup Thursday that the Senate NDAA language made him “a happy man.”

The House NDAA now heads to the Senate. If history is a guide, the Senate will substitute its own NDAA language on the floor ahead of a bicameral conference committee in which the chambers will hash out their differences.

Over the course of the week, House Republicans united to shoot down several amendments that would have checked the funding increases and new warhead work the bill authorizes for NNSA.

Reps. Earl Blumenauer (D-Ore.), John Garamendi (D-Calif.), and Peter Welch (D-Vt.) offered an amendment that would have fenced off half of the $65 million in funding the NDAA authorized for the proposed low-yield warhead until the Pentagon reports to Congress about how the weapon might affect global military stability. The amendment failed 188-226 on Wednesday. All but seven of the Democrats who voted supported the amendment, while only five Republicans crossed the aisle.

Also defeated along party lines this week was an amendment proposed by Rep. Pete Aguilar (D-Calif.) that would have required the White House to add a 20-year cost estimate for ongoing nuclear-weapon programs to an annual report it delivers to Congress along with each year’s federal budget request. Aguilar’s amendment went down 198-217, with nine Republicans voting yes and only a single Democrat voting no.

An amendment from Rep. Jared Polis (D-Colo.) and Blumenauer would have reduced the funding authorized in 2019 for the NNSA’s defense programs office by about $200 million to roughly $11 billion: the amount the administration requested. The amendment was defeated Wednesday along a somewhat narrower party-line vote: 174-239.

The House did adopt an amendment from Rep. Ben Ray Luján (D-N.M.) and two New Mexico colleagues to ratchet up oversight of the NNSA plutonium pit program. Co-sponsored by Reps. Steve Pearce (R-N.M.) and Michelle Lujan Grisham (D-N.M.), the amendment would require a Federally Funded Research and Development Center — one not owned by the Department of Energy — to assess the NNSA’s future plutonium plans and deliver a report to Congress by April 15. That report would include a review of the engineering analysis the agency cited as justification for the two-pronged pit-program announced earlier this month.