WASHINGTON ― Congress will begin formal negotiations on a compromise defense policy bill this week, with final votes likely to occur before the holidays.

The annual bill is usually a bipartisan product, but conference committee talks over the fiscal 2024 National Defense Authorization Act may be trickier than usual this year. House Republicans added numerous partisan provisions from the right-wing Freedom Caucus to their version of the bill. The Senate version contains several of its own amendments that enjoy bipartisan – though not always unanimous – support.

The House passed 219-210 its $874 billion defense policy bill largely along party lines in July after Democrats defected when Republicans added the Freedom Caucus amendments. Later in July, the Senate passed 86-11 its $886 billion defense policy bill without the socially conservative provisions.

Both bills nonetheless have significant areas of overlap, some of which have generated opposition from the White House. These provisions include the procurement of an amphibious transport dock ship and language institutionalizing the sea-launched cruise missile nuclear program. Less controversial items in both bills include a provision to deepen counter-fentanyl cooperation with the Mexican military and require the Pentagon to coordinate with Taiwan on cybersecurity.

The conference committee must still sort through the differing provisions from each chamber as it hammers out a compromise bill that can pass both the Republican-controlled House and Democratic-held Senate.

Here are some of the key differences lawmakers will need to resolve to make that happen.

Freedom Caucus amendments: In order to secure Freedom Caucus support to pass the House bill, Republicans voted to add several of their amendments. These amendments would overturn the Pentagon’s abortion leave policy, restrict medical care for transgender troops, eliminate military diversity initiatives and block the Defense Department from implementing President Joe Biden’s seven climate change executive orders.

Democrats cited their opposition to these measures as part of their reason for joining Rep. Matt Gaetz, R-Fla., in his ouster of former Speaker Kevin McCarthy, R-Calif. While removing these amendments would restore Democratic support for what is usually bipartisan legislation, it remains to be seen whether House Republicans would allow a vote on such a compromise bill.

Ukraine Inspector General: A House provision added by Gaetz would establish an independent inspector general to oversee Ukraine aid. The White House opposes creating this position, and the Biden administration is almost out of money to continue arming Kyiv. The defense bill aside, it’s also unclear whether Congress will pass Biden’s separate $61 billion Ukraine aid request for FY24.

AUKUS: The Senate bill includes two provisions from Sen. Bob Menendez, D-N.J., needed to implement AUKUS, the trilateral submarine-sharing pact with Australia and Britain. One authorization would allow the U.S. to begin training Australian private sector personnel to use nuclear-powered submarines while the other provision would allow the State Department to loosen export controls for Canberra and London.

Sen. Roger Wicker of Mississippi, the top Republican on the Armed Services Committee, blocked two other key AUKUS authorizations from the bill: one that would allow the transfer of Virginia-class submarines to Australia and another that would allow the Biden administration to accept Australia’s $3 billion contribution in the U.S. submarine-industrial base.

Wicker has demanded more money for the submarine-industrial base before lifting his two AUKUS holds. While Wicker has spoken positively of Biden’s $3.4 billion request to expand submarine-industrial base capacity as part of a broader defense supplemental spending package, it remains to be seen whether he’ll allow the final two AUKUS authorizations in the final defense policy bill.

NATO: Senators adopted 65-28 an amendment from Sen. Tim Kaine, D-Va., that would require Senate approval if a president tries to withdraw the U.S. from NATO. Former President Donald Trump, the frontrunner in the Republican presidential primary, threatened to withdraw from NATO in 2018 if U.S. allies did not meet their commitments to spending 2% of GDP on defense.

Buy America: Senators unanimously agreed to an amendment from Sen. Tammy Baldwin, D-Wis., mandating that 100% of components for all Navy ships be manufactured in the U.S. by 2033. Baldwin’s amendment would allow the defense secretary to wave those requirements under certain circumstances.

Chief Management Officer: A provision from Sen. Joe Manchin, D-W.Va., would revive the Pentagon’s short-lived chief management officer, a position tasked with reforming defense business practices that ranked No. 3 in the Defense Department until Congress abolished it three years ago. The White House opposes reviving the office.

Cost assessment office: House Republicans included a provision in their bill that would abolish the Pentagon’s Cost Assessment and Program Evaluation Office and move its duties elsewhere, citing the office’s role in the Defense Department’s decision to pause amphibious ship purchases. The Senate bill would not abolish this office.

Space Command headquarters: Both bills include a now-dated provision intended to force the Pentagon to make a decision on a final location for the Space Command headquarters. The Biden administration announced in August that it wished to place the headquarters in Colorado Springs, Colorado, revoking a previous decision to locate it in Huntsville, Alabama. The Republican House Armed Services chairman, Mike Rogers, is from Alabama. It remains to be seen if the final bill will include updated stipulations on the final location for Space Command after a years-long dispute.

Bryant Harris is the Congress reporter for Defense News. He has covered U.S. foreign policy, national security, international affairs and politics in Washington since 2014. He has also written for Foreign Policy, Al-Monitor, Al Jazeera English and IPS News.

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