Possible Clues:

• China invades America, so POTUS may be called
• Word made up of initial letters
• NAACP, for one
• Possibly scuba buddy's inside empty aquarium
• Acorn with slight mutation arising, my word, that's initially important
• Initial combination that's familiar in a mass
• What comes from opening letters, thousand written by a mate
• A close friend beginning to mistrust NATO, for example
• Pronounceable word or name formed from initial letters of others
• A sequence of initial letters or parts of words, pronounced as a word, such as Awol, Radar, or Scuba