I catch myself doing this from time to time.
If an asteroid were to head toward the earth, that threatened all life everyone would be given the option to set aside differences and get along for a moment or die. The aftermath would be a period of time when people didn't fight as much. Everyone would be united and peaceful, even if it were just a moment of time because of a threat directed to everyone.
I used to have a habit [bad or good depending on how you look at it] of doing this on purpose to friends of mine when they fought over trivial things and were too stubborn and prideful to say sorry. I would end up doing something to piss off all the friends who were pissed at each other, they'd get pissed at me and try to get me back or just talk about how much of an asshole I was. The end result was usually them hating me, but no longer hating each other.
This was usually something I did if I was moving away. I'd be hatefully remembered but at they would no longer hate each other.