Under Siege (1992)

"In 1992 a battleship's been sabotaged by nuclear pirates out to steal its warheads. Now, surrounded by terrorists, a lone man stands with a deadly plan of attack."

A disgruntled ex-CIA operative, his assistant and their assembled group of terrorists seize a battleship with nuclear blackmail in mind. They've planned for every contingency but ignore the ship's cook, former Navy SEAL Casey Ryback—an error that could be fatal.