Quote from 377OHMS:
I've launched American rockets from Kennedy, Cape Canaveral and Vandenberg, European rockets from French Guiana, Chinese rockets from Xichang, Japanese rockets from Tanegashima and Russian rockets from Kazakstan and from a floating launch platform in the Pacific at 154-deg West.
I've worked with ICBM boosters and have personally hand-armed a 7500 lb MinuteMan upper stage in the cargo bay of the space shuttle used to circularize the orbit of a large satellite.
This looked like an SLBM. It looked American. The plume color, ascent angle and rotation looked familiar. Nobody launches West (retrograde) except ICBMs. Everything else is launched East (commerical and shuttle) or North (spy stuff in polar orbits). I saw no staging, no separations, no shroud ejection.
I would say it was a Navy SLBM test launch towards either PMRF (Kauai) or Kwajalein in support of the Missile Defense program.