Definition of SAFE HAVEN from a DOD web site document:
Safe Havens - Space that provide a secure base for extremist action, including:
Physical space - failed/failing states, under-governed areas and sponsors who provide safe areas where terrorists train and organize. Many safe havens sit astride international borders, demanding a regional, rather than solely national response.
Cyber space- electro-magnetic and internet-based means for communication, planning, resource transfer and intelligence collection. These means allow terrorists to organize, communicate, spread propaganda and transfer money.
Ideological space - belief systems, ideas and cultural norms that enhance the enemy's freedom of action. These include ethnic identities, religious attitudes and political cultures.