WASHINGTON — The Obama administration's defense secretary nominee says he cannot execute the existing national defense strategy if more across-the-board budget cuts occur.

Ash Carter, a former deputy defense secretary, told the Senate Armed Services Committee on Wednesday he believes "the strategy is not executable under sequestration-level budget caps."

In written responses to questions posed in advance by the committee, Carter explained how he will gauge whether the US military is getting ample funding.

"The measure must be, can the department meet the security challenges of today, while also investing adequate resources to prepare for future security challenges, both the expected and the unexpected," Carter says.

"There has to be balance," he added. "The department should have sufficient capacity to deal with the wide range of challenges we face, yet not maintain more capacity than we can afford to modernize and keep ready, given that we also have a responsibility to the force of the future."

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The president's 2016 budget calls for $35 billion more than spending caps allow at $534 billion, and his future years defense plan — the Pentagon's five-year planning document — is slated to leap over the caps set in place from 2016 through 2020 by $155 billion, according to budget documents released on Monday.

SASC Chairman Sen. John McCain, R-Ariz., and Ranking Member Sen. Jack Reed, D-R.I., both cited the sequester cuts among the myriad challenged Carter would face if confirmed by the full Senate. Reed called the automatic cuts to non-exempt accounts "mindless."

"Despite the growing array of complex threats to our security, we are on track to cut $1 trillion out of America's defense budget by 2021," McCain said.

"Readiness is falling across the services, and morale is falling right along with it. Army and Marine Corps end-strength is dropping dangerously low," he said. "The Air Force is the oldest and the smallest it has ever been. The Navy's fleet is shrinking to pre-World War I levels. And last week, each of our service chiefs testified before this Committee that American lives are being put at risk due to sequestration.

"Sequestration represents a failure to meet our most basic constitutional responsibility to provide for the common defense," McCain added. "America's military can no longer be held hostage to domestic political disputes totally separated from the reality of the threats we face. … Rolling back sequestration is necessary to provide our military the strategy-driven budget necessary to confront the threats we face."

While McCain and other congressional defense hawks want to dramatically lessen or totally eliminate the defense portion of the remaining sequester cuts, they are the only ones pushing the idea on Capitol Hill.

Both Republican and Democratic leaders are focused on other things, as are their hand-picked chairs and ranking members of the Budget committees.

What's more, analysts say the politics that have prevented passage of the kind of fiscal deal that would address sequestration remain in place.

The heads of the House and Senate Budget committees, who soon will craft a 2016 budget resolution that could raise spending caps, have said nothing about giving the Defense Department more funding since their secured their gavels last month.

Meanwhile, McCain said he is concerned that the White House will push him to the fringes — or exclude him from — decision-making.

"I must candidly express concern about the task that awaits you, if confirmed, and the influence you would have on some of the most critical national security issues facing our nation," McCain said. "Two of your predecessors, Secretary [Robert] Gates and Secretary [Leon] Panetta, have severely criticized White House micromanagement of the Defense Department and over-centralization of foreign and defense policy.

"According to numerous news reports, Secretary [Chuck] Hagel experienced similar frustrations with the insular and indecisive White House national security team over issues ranging from [the Islamic State] to Ukraine, detention policy to sequestration," McCain said. "Dr. Carter, I sincerely hope the president who nominated you will empower you to lead and contribute to the fullest extent of your abilities."

Carter later assured the committee, if confirmed, "I will be a stickler for the chain of command."

"I have promised President Obama that if I am confirmed, I will furnish him my most candid strategic advice," Carter said. "I will also ensure that the president receives candid professional military advice. This is not only consonant with the law as written in this very committee, but with good sense, since our military leaders possess wide and deep experience and expertise."

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