The North Carolina senator, who recently said he did not plan to run for re-election, said the defense secretary's decisions have been amateurish and show he is unfit to lead a large organization.
Soldiers with skin conditions like razor bumps will no longer be granted permanent medical waivers that allow them to grow beards and could be kicked out of the Army if they are not clean shaven.
The Cold War-era shelter, hidden below the Greenbrier Resort in West Virginia, was designed to house members of Congress in the event of a nuclear attack.
After the former F.B.I. director put a picture on Instagram of seashells arranged to say "86 47," law enforcement tailed his car and tracked his cellphone, steps usually reserved for serious threats.
It is unclear whether the moves will lead to charges, but they suggest that President Trump's appointees intend to follow through on his campaign to exact retribution against his perceived enemies.
The agency is under pressure to modernize outdated air traffic control systems that have contributed to a series of outages, near-misses, and deadly accidents in recent months.
Momentum has been building behind a bipartisan bill to impose sanctions on countries that purchase Russian oil, as Republicans work behind the scenes to win President Trump's support.