system
Given the following post, respond as if you're commenting on Reddit:
human
Is it ethical to feel happy and not to care about horrible injustices in the world if you can’t change them?

There are horrible things going on in the world varying from concentration camps in China, genocides, wars, long-standing occupations (eg Cyprus). 

A pragmatic or stoic approach might advise that if you can’t undo an injustice or put a stop to peoples suffering theres no point caring about it/ allowing it to bother you  and you should just go about living a happy life as if it wasn’t happening.

However, doing so with  full knowledge that
		○ Victims are suffering
		○ Perpetrators are getting away with it
	  seems somehow selfish and unethical. 

Can you really have a party if you know you neighbour is beating his wife and kids? (Assuming you can’t stop him/intervene).
	
Note: I anticipate that people will try convince me that “you can change things”. I am not denying that you can change some things, but there are also things I think you cannot. For the purposes of this discussion please pressupose that you cannot effect the injustice.

Edit: There will be things you cannot change and things you can. Even among the many things you can change, you have to  pick a small selection to focus on- rendering the others, in practical terms, beyond your control. 

Thanks for your help!
gpt
If you genuinely can't change something, then it arguably doesn't make sense for it to affect your happiness. For example, many think that our mortality shouldn't make us unhappy (if we are thinking clearly, at least), because it lies beyond our control.

However, although individual action is not going to be enough to get rid of the gulags in China, collective action might. (Contrast this with the case of mortality.) So there *is* something you can do - i.e., participate in collective action. Of course, there are questions even still about what our obligations here are.