WASHINGTON — U.S. President Donald Trump may be signing executive orders at a furious pace, but for defense spending, the White House and Congress are looking ahead to a thorny agenda and a shrinking schedule. 

Top of the list is the overdue 2017 defense appropriations bill, which lawmakers punted with a continuing resolution last year that expires April 28. That deadline is likely to come sandwiched between a Trump budget amendment that favors defense and the White House's 2018 budget request.

But none of it is the main event on Capitol Hill. For Congress, the real battle royale is over Trump nominees, including Supreme Court nominee Neil Gorsuch, and the repeal and replacement of the Affordable Care Act. Democrats don't have the votes to block Cabinet appointees, but they're showing they will use procedural maneuvers to delay the Republican agenda.

"We're set up to have several months of just chaos when it comes to the budget," said Todd Harrison, director of defense budget analysis at the Center for Strategic and International Studies.

"All of these other things are just going to suck the air out of the Capitol," with little stamina left for the 2017 and 2018 budgets, he added.

Armed Services committee leaders in both chambers are pressing to take up and pass the 2017 defense spending bill, but for Senate Armed Services Chairman John McCain, R-Ariz., the schedule pressure and the lack of a clear path mean it isn't a foregone conclusion. 

McCain suggested that if Trump can't make a deal that includes enough domestic spending for Democrats to support it, Congress might punt to a full-year continuing resolution that the defense community won't like.

"It's a real possibility unless we get the president's understanding that you can't necessarily cut everything else to pay for defense. That will probably not get enough votes," McCain said.

To increase defense spending, any budget deal must chart a course through Senate Democrats who'll want parity between defense and non-defense spending, and fiscal conservatives — including the administration's presumptive budget director, Rep. Mick Mulvaney, R-S.C., who has historically taken a dim view of using emergency wartime funds to skirt budget caps.

House Armed Services Committee Chairman Mac Thornberry, R-Texas, and McCain are proposing a separate $640 billion base budget plan for 2018 defense spending.

Thornberry told reporters Jan. 6 he wants Congress to take up 2017 defense appropriations "as soon as possible" and that "there is no reason in the world not to finish this year's budget."

Thornberry said the administration has been "very clear and consistent that they will send up a supplemental request for '17 within the first 100 days." He has suggested the Trump administration start with the $18 billion in jets, ships and manpower that the House approved but that were dropped from last year's annual defense policy bill.

"A lot of the challenge is we don't have [a budget] director," Thornberry said. "Yeah, you can have conversations with the administration, but we're still trying to get the meat."

Waiting for the administration's top line for defense threatens to push the Armed Services committees' drafting of their annual defense policy bill ever later. "Obviously we're doing our homework now, so we're not waiting on their budget request to begin our work," Thornberry said. 

In an argument seemingly aimed at fiscal conservatives, Thornberry said: "You do not balance the budget by cutting defense," adding that defense spending cannot wait "until we get all of our budget problems solved."

Thornberry also argued against holding defense spending "hostage" to domestic spending. "That is absolutely wrong, morally, and every other way," he said. "Senators will use the argument, but it's wrong."

By budget season, Defense hawks will be able to wield a Defense Department readiness review — ongoing for now — that will inform the budget amendment and make the case to increase defense spending, Harrison said. 

"They could do a CR and pass a supplemental on top of it, but it's a clumsy way to do it, and if you're going to do that, you might as well pass a regular defense appropriations bill," he said.

What won't help the cause later on is that three weeks into the administration, the Senate has confirmed only a handful of Cabinet nominees, and that Trump has not named many of his mid-level picks. Calendar-eating Democratic delay tactics are partly to blame, as is the Trump administration's slow start filling DoD positions.

Late last month, Army secretary nominee Vincent Viola abruptly withdrew his name from consideration over business entanglements, while Air Force secretary pick Heather Wilson and Navy secretary pick Philip Bilden were only recently named.

McCain, who has signaled his committee will clear DoD candidates for a full Senate vote as soon as possible, said Wilson's name was official but Bilden's is not. "I wish they'd move forward."

"I'm concerned about all of them," McCain said. "Also, the Democrats are slowing it so much that it's almost irrelevant whether we get the names. It's the slowest process since Abraham Lincoln."

Joe Gould is the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He served previously as Congress reporter.

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