The slow pace of confirming Trump administration nominees shows no signs of abating at the Pentagon as mid-October rolls around and 70 percent of its top posts remain unfilled.

Just 17 of the 57 Pentagon positions that require Senate confirmation have been filled by President Trump's appointees. That figure has barely budged in two months, leaving the military without a spectrum of leaders who can put the administration's stamp on policy.

"I think we should be very concerned and informal reports I get from the Pentagon suggest that this is a problem, that this is not just like business as usual over there," said Thomas Spoehr, the director of the Center for National Defense at the Heritage Foundation.

The White House, which had been slow to name nominees, rolled out three more names this week, including John Rood, a senior vice president at defense giant Lockheed Martin, for undersecretary of defense for policy.

In all, 23 of Trump's nominees are somewhere in the confirmation pipeline, either named or awaiting action by the Senate, but 17 Pentagon-appointed positions still do not even have candidates named by the president.

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The Senate Armed Services Committee, which has purview over vetting Defense Department nominees, has become a major bottleneck for Trump.

Sen. John McCain, R-Ariz., the committee chairman, has said he is holding Army secretary nominee Mark Esper, a top lobbyist for defense contractor Raytheon, and others because he wants the Trump administration to provide information on military operations in Afghanistan and Iraq.

McCain's committee has not held a confirmation hearing — other than for the reappointment of Joint Chiefs Chairman Gen. Joseph Dunford — since July. Of the 23 nominees somewhere in the confirmation process, 16 of those are currently parked at the Armed Services Committee.

Defense Secretary Jim Mattis and Dunford both testified to Armed Services on Oct. 3 about the situation in Afghanistan.

But the committee, which was out of town along with the rest of the Senate over the past week, had not moved on any nominees. No hearing for Esper had been scheduled by Friday.

Spoehr said McCain and his committee could potentially approve the waiting Trump nominees quickly, vetting four or so per hearing.

For now, the Pentagon may be fine holding the status quo without the 40 positions filled but the appointees will be needed to implement the agenda of Trump and Mattis.

"If you actually want to make changes, if you want to do things differently … you've got to have these political appointees and not just at the top but at all the various echelons," Spoehr said.