For Calamity Tax if first understand meaning of Calamity:
It means a great misfortune or disaster, rievous affliction; adversity; misery: the calamity of war such as
- Avalanches and landslides.
- Earthquakes.
- Sinkholes.
- Volcanic eruptions.
- Floods.
- Limnic eruptions.
- Tsunami.
- Blizzards
So Calamity tax means goverment impose Tax for helping states that suffer with above disasters.
Calamity tax = Calamity + Tax to fight it
Calamity declared as a national calamity is qualified for this tax. Further goverment need to take a decision wether to impose a tax for that national calamity or not.
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