Gadzooks! Ya’ll check out... 
the US Navy's Liberdade XRay at http://www.onr.navy.mil/media/extra/fact_sheets/advanced_underwater_glider.pdf
I wonder if some day we’ll have stealthy, inter-continental, UNDERWATER missiles...totally invulnerable to SDI countermeasures...?
Gadzooks! Ya’ll check out... the US Navy's Liberdade XRay at http://www.onr.navy.mil/media/extra/fact_sheets/advanced_underwater_glider.pdf