OVERNIGHT DEFENSE: Congress seeks answers to Boston bombings

“I have great faith that an arrest is going to be made,” said Senate Intelligence Committee Chairwoman Dianne FeinsteinDianne FeinsteinJustice requires higher standard than Sessions Senate to vote Friday on Trump's defense picks Senate seeks deal on Trump nominees MORE (D-Calif.). “I don’t think it’s going to be the day after tomorrow, but that’s OK. It’s going to happen.”

President Obama called the “heinous and cowardly” bombing an “act of terrorism,” and Attorney General Eric HolderEric H. HolderTrust Women opposes Sen. Session's nomination Former AG launches redistricting effort to help Dems reclaim power The racism inquisition over Jeff Sessions MORE said a full-scale investigation is underway.

“Although it is not yet clear who executed this attack, whether it was an individual or group, or whether it was carried out with support or involvement from a terrorist organization — either foreign or domestic — we will not rest until the perpetrators are brought to justice,” Holder said.

Defense Secretary Chuck HagelChuck HagelWho will temper Trump after he takes office? Hagel: I’m ‘encouraged’ by Trump’s Russia outreach Want to 'drain the swamp'? Implement regular order MORE made reference to the attack in his opening remarks at a congressional hearing Tuesday, calling it a “cruel act of terror.”

“An event with multiple explosives devices is clearly an act of terror and will be approached as an act of terror,” he said.

Hagel and Joint Chiefs Chairman Gen. Martin Dempsey are being briefed on the developments, a senior defense official said, and Dempsey said Tuesday the military was ready to assist if needed.

Dunford balks on Afghan postwar numbers: The Pentagon's top officer in Afghanistan backed off claims the U.S. will need more than 13,000 American troops in country after next year.

Gen. Joseph Dunford's decision put him back in the White House's camp on the question of how many American troops to leave in Afghainstan after the administration's 2014 withdrawal deadline. But it also indicated possible friction between U.S. field commanders and the White House. 

Dunford "is getting a lot of pressure from political people to pick a number less than 13,600," Sen. Lindsey GrahamLindsey GrahamThe Hill's 12:30 Report Graham: Trump would make mistake in not punishing Russia Graham to vote for Trump’s EPA pick MORE told reporters after the hearing, after the four-star general's testimony before the Senate Armed Services Committee. 

"I can tell you, the number will matter," Graham (R-S.C.) said. "If the number is too small, we will fail." 

In March, Dunford and U.S. Ambassador to Afghanistan James Cunningham reportedly told House Armed Services Committee chief Rep. Buck McKeon (R-Calif.) they supported a postwar recommendation for 13,600 troops in Afghanistan. 

President Obama has reportedly championed a postwar U.S. force of between 8,000 to 10,000 troops. Chairman of the Joint Chiefs of Staff Gen. Martin Dempsey has also publicly supported the smaller range of troops. 

"I have never publicly talked about numbers ... never have," Dunford told The Hill when asked why he backed off his support for the troop recommendations. However, the four-star general did not deny that he had conveyed his support for the 13,600-man force to McKeon during his visit to Afghanistan in March. 

Said Graham: "When our generals tell us that 13,600 is sort of the right number, the bottom line number, I hope we do not deviate too much from that."

During Tuesday's hearing, Dunford took heavy flak from committee Republicans for refusing to outline his postwar plans. "I can't tell you how disappointed I am in your testimony, general," Sen. John McCainJohn McCainSenate committee to vote Monday on Tillerson Trump fails to mention Clinton in inaugural address Hillary Clinton under microscope at inauguration MORE (R-Ariz.) told Dunford. 

The panel’s Democratic chairman, Sen. Carl LevinCarl LevinObama to preserve torture report in presidential papers 'Nuclear option' for Supreme Court nominees will damage Senate McCain's Supreme Court strategy leads to nuclear Senate MORE (D-Mich.), defended Dunford's decision to remain mum on U.S. postwar plans in Afghanistan. 

"There are certain things that he needs to put in place before he makes his recommendations," Levin told The Hill after the hearing. 

More drones, less troops: As the number of U.S. troops in Afghanistan drops, the number of American drones in the country must increase, the top U.S. commander in the region told Congress on Tuesday. 

"I will need a sustained [intelligence, surveillance and reconnaissance] effort post-2014," Gen. Joseph Dunford told members of the Senate Armed Services Committee.

"In fact, at the time that we reduce forces, [unmanned drones] actually become as important or more important," the four-star general said during the Tuesday hearing on the current state of the Afghan war. 

The aggressive use of armed drones in Afghanistan has played a significant role in turning the tide of the conflict, according to Dunford.  

"I would tell you that the Taliban are very concerned about those vehicles, and they talk about them all the time," he told committee members. 

However, he did acknowledge the tremendous toll those drone operations take on Afghan civilians. 

"Even if we're doing it perfectly, if it creates, you know, a great deal of controversy within a civilian community," Dunford admitted, "that can make our challenge more difficult down the road." 

But under reductions to the department's drone programs in the fiscal 2014 budget plan, the services might not have enough assets to support Dunford's postwar demands. 

Pentagon officials slashed spending on unmanned drones across the board, cutting just over $1 billion from those programs in the department's newest budget proposal for fiscal 2014.  

The drone cuts were part of the $45.4 billion request for all military aircraft in the department's spending plan, sent to Congress on April 10. 

BRAC is bust, says Levin: Senate Armed Services Comittee Chairman Carl Levin (D-Mich.) says the Pentagon didn’t “put their money where their mouth is,” and doesn’t see their proposal for a new round of base closures gaining any traction in the Senate this year.

The Pentagon included $2.4 billion for base closures in this year’s Defense budget, but Levin told The Hill that he didn’t think the money added up to much because none of it was included in the 2014 budget, only in 2015 and beyond.

“They didn’t put their money where their mouth is this year — they put their money where their mouth is next year,” Levin said. The Pentagon in its 2014 budget proposed beginning a new round of base closures in 2015, with the bases not being shuttered until 2016.

The Pentagon included $2.4 billion to pay for the new round of the Base Closure and Realignment Commission (BRAC), as closing bases requires an up-front cost before generating savings.

That was a step up from the 2013 budget request, when there was no money included for two rounds of base closures and lawmakers quickly dismissed it.

But lawmakers were hostile to the idea of new base closures even before the budget came out, saying it was an unnecessary step at a time when Pentagon budgets were trim.

The Pentagon argues that infrastructure cuts are needed because the department already has more than 20 percent excess infrastructure, a number that will continue to grow as the number of service members is reduced.

It remains to be seen if Congress will buy that argument.

In Case You Missed It: 

— Hagel calls Boston bombings 'cruel act of terror' 

— Pakistan not sandbagging Taliban peace plans, says Dunford

— DOD needs to do more on China cyberattacks

— China slams US military buildup in Pacific

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