Columbia subject headings:
Harvard subject headings:
IS (Organization)
Islam and world politics.
Islamic fundamentalism--History.
Jihad
Terrorism--Europe
Terrorism--Religious aspects--Islam
Princeton subject headings:
IS (Organization)
Islamic fundamentalism--European Union countries--21st century.
Islamic fundamentalism--Political aspects.
National security--European Union countries.
Terrorism--European Union countries.
Terrorism--Middle East.