Merchant marine Prevention Security measures 10 Shipping 8 Maritime terrorism 7 Piracy 6 Hijacking of ships 4 more ... Security, International 4 Pirates 3 Safety measures 3 Container ships 2 Economic aspects 2 Freedom of the seas 2 Law and legislation 2 Law of the sea 2 Passenger ships 2 Terrorism 2 Armed merchant ships 1 Effect of terrorism on 1 Emergency management 1 Fast attack craft 1 International cooperation 1 International trade 1 Liquefied gases 1 Naval convoys 1 Navigation 1 Private military companies 1 Private security services 1 Transportation 1 Unified operations (Military science) 1 less ...