Army can be used for Protection. Army is related to Police. Police is part of Government. 
Reach entails/necessarily involves Travel. Reach is a synonym of Gain. Gain is the opposite of Reduce. Reduce is related to Loss. 
Protection <--UsedFor-- Army <--RelatedTo--> Police --PartOf--> Government 
Travel <--Entails-- Reach <--Synonym--> Gain <--Antonym--> Reduce <--RelatedTo--> Loss 