WASHINGTON — The U.S. House on Wednesday took up a defense appropriations bill that proposes tens of billion of dollars in new spending for the Pentagon. The problem is it breaks budget caps set in law.

The House’s version of 2018 defense appropriations legislation includes added ships, jets and potentially $28.6 billion in flexible funding for emerging requirements. At $584.2 billion, with $73.9 billion overseas contingency operations, or OCO, it would exceed 2018 budget caps for defense by $63.5 billion.

Some lawmakers fear that with no clear path from GOP leaders to adhere to or lift the budget caps, it’s unclear whether Congress is headed toward sequestration budget cuts triggered when the caps are broken or some other scenario that would damage defense.

“It’s headed toward a colossal crackup,” House Armed Services Committee ranking member Adam Smith, D-Wash., said Wednesday. “Understand that the legislation they have put forth is the most craven piece of legislation I have witnessed in 20 years.”

Smith, who has been railing against what he sees as defense budget dysfunction, ripped “hypocritical” House Republicans who want to be both pro-defense and fiscally conservative.

“They are passing a bill that will be null and void in order to both say, ‘I didn’t vote to lift the caps, and I did vote for more defense spending,’” Smith said. “This is an enormous waste of time, all because they don’t want to honestly address the issue. Which of these things are ultimately going to give?”

The House has taken up defense appropriations packaged in a four-bill, $790 billion “security bus” that also includes spending bills for energy and water, the legislative branch, military construction and Veterans Affairs.

Democrats have voiced opposition to the legislative vehicle, arguing it short-circuits debate on domestic priorities as well as its likely inclusion of funding for a border wall. 

The 2011 Budget Control Act caps the Pentagon base budget, Department of Energy nuclear spending and other defense-related spending combined at $549 billion for fiscal 2018.

The president’s budget request, at $603 billion, exceeds the caps by $54 billion; and the House and Senate defense appropriations committees exceed them by $63.5 billion and $1.8 billion, respectively.

Although the annual National Defense Authorization Act, as a policy bill, is not subject to budget caps, the versions passed by the House and Senate armed services committees exceed the caps by $71.9 billion and $90.7 billion, respectively.

Pro-defense lawmakers have argued the president’s budget request is not enough. Texas Republican Rep. Kay Granger, who chairs the House Appropriations Defense Subcommittee, nodded to a warning from Defense Secretary Jim Mattis to Congress that the military will lose its edge without consistent funding.

“We must keep this funding intact,” Granger said on the House floor on Wednesday. “We need to heed secretary Mattis’s warning and give our military what it needs, no less. This is not a partisan issue.”

House Armed Services Tactical Air and Land Forces Subcommittee Chairman Mike Turner, R-Ohio, and other lawmakers have pressed House Speaker Paul Ryan, R-Wis., for a vote to repeal budget caps for defense alone. On Wednesday, Turner said the effort was active and that GOP leaders “are just looking for the votes.”

“We’re trying to give them all the assurances that we can that the votes are there,” Turner said.

House Seapower and Projection Forces Subcommittee Chair Rob Wittman, R-Va., said defense authorizers and appropriators are pressuring House GOP leaders to significantly plus-up defense, “one way or another.”

“It’s up to leadership to negotiate it, but the message has come pretty strongly from appropriators and authorizers that this is where we need to be,” said Wittman. “Because of [budget caps] and the impact it’s had on readiness and the devolution of readiness, we find ourselves in this position.”

To lift or ease the caps would also require the support of Democrats, who have demanded defense increases be matched in the nondefense side of the budget. That, in turn, would cost support from GOP fiscal conservatives.

Congress has in recent years used OCO, which is exempt from the caps as a wartime fund, as a relief valve for spending unrelated to war. But lawmakers have expressed concerns that White House budget director Mick Mulvaney, a deficit hawk during his time in Congress, may use his authority to block miscategorized defense spending.

The Center for International Policy’s William Hartung said in a report published Wednesday that using the war budget to accommodate increases proposed in the House and Senate Armed Services committees is “unlikely,” as OCO would have to be more than doubled. He called various defense spending proposals “fantasy budgeting.”

“With proposals that exceed the budget caps by anywhere from $54 billion to $91 billion, the plans put forward by the Trump administration and key congressional committees are an exercise in fantasy budgeting. The chances for a budget deal that can accommodate these levels of spending are between slim and none,” Hartung said.

“Only the defense subcommittee of the Senate Appropriations Committee has come in with a realistic proposal that is close to the caps and, therefore, a more reasonable target for topline spending in the budget maneuvers to come between now and the end of the year.”