Possible Clues:

• Invincible organisation with a small crew is competent
• Impregnable base in USA, all newly set out
• Girl’s description of operational ship impervious to attack
• Secure redeployment of all in a US base
• Unable to be attacked
• Can¿t get over this can¿t be attacked
• Woman's having trouble fitting into warm coat that's stormproof?
• Allies ban USA's renegotiation as being out of reach