One of the most highly respected military officers of his generation went before the Senate on Thursday to face questions about the constitutional propriety of his holding the most important post in the US defense establishment.

There was little Senate opposition to the recently retired marine general James Mattis becoming secretary of defense; both Democrats and Republicans unsettled by Donald Trump’s inclinations on national security consider Mattis to be a familiar and stabilizing factor.

But “Mad Dog” Mattis retired from the Marine Corps in 2013, meaning he falls well short of having notched up the required seven years out of uniform before a member of the military can run the Pentagon – a requirement that underpins the subordination of the military to civilian control enshrined in the constitution.

The Senate Armed Services Committee approved the waiver for Mattis with a vote of 24 -3. Senator Elizabeth Ann Warren (D-MA), Senator Kirsten Gillibrand (D-NY), and Senator Richard Blumenthal (D-CT) opposed the waiver.

Mattis’ ascension is not yet guaranteed. He still needs approval from the Senate and the House.

Popular Military contributed to this report

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