Just everyone with a gun or a jail or a vehicle for transport.
Everyone who has the means to investigate a crime, the authority to charge a crime, or who owns a prison to punish a crime, works for POTUS.
Except Congress is Constitutionally Authorized to withhold funds, and impeach/convict/remove.
Any/every POTUS who chooses to ignore a Federal Court order can do so with impunity absent impeachment.
> “Just everyone with a gun or a jail or a vehicle for transport.”
Nope. Courts have jails connected to them that they control.
A portion of US Marshals are assigned to and work for federal courts and act on orders of federal judges.