TrenchWar

1. weapons

1.1. tanks

1.2. machine guns

1.3. barbed wire

1.4. aritillery

2. tactics

2.1. gas attacks

2.2. preparatory bombardment

3. causes

3.1. industrialization

3.2. advanced defensive weaponry

4. life in the trenches

4.1. In the trenches there were rat infestations

4.2. Death

4.3. Trench fever

4.4. Trench foot

5. emotions

5.1. Anxiety attacks

5.2. Shell shocked which has similar effects as PTSD