Dic: [countable] cause (as an aim or principle)

1. 
[Countable] A cause is an aim or principle which a group of people supports or is fighting for. cf. lost cause.
[Countable] an organization or idea that people support or fight for.

• Refusing to have one leader has not helped the cause. 
• Animal welfare campaigners raised £70000 for their cause last year.
• a good cause (=an organization that does good work, such as charity)
• fighting for the Republic cause.
• The donation is the biggest private gift to a humanitarian cause.

..... COBUILD, OALD

2.
cause

• (3) the ideals, etc... of a group or movement: ex) the Communist cause
• (4) the welfare or interests of a person or group in a dispute: ex) they fought for the miners' cause
• (5) a matter of widespread concern or importance: ex) the cause of public health

.... COLLINS

3.
have(make) common cause:

• to join with (a person, group, etc.) for a common objective.
• to join with other people or groups in order to oppose an enemy .

...  COLLINS, LDOCE

* * *

CF. [Uncountable: N for n, N to-inf] cause: If you have cause for a particular feeling or action, you have good reasons for feeling it or doing it.

• Only a few people can find any cause for celebration...
• Both had much cause to be grateful for the secretiveness of government in Britain.

CF.

• White wrote his draft at a bad moment for the Allied cause.
  (화이트의 초안은 연합국들이 뜻을 모으기에는 좋지 않은 시점에 나왔다.)
  (...)
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