Regarding the event of a contact with an alien civilization, we usually have 2 scenarios: war or salvation for whatever problem we have. Both are extreme, but the outcome is quite simple: Change. A change that has both of war and of salvation.
War requires an aggressive civilization. Aggressive civilizations can’t maintain themselves for long periods of time, they tend to get devised and to resent technological, political and social advances. In the immensity of space, it’s hard to believe that aggressive civilizations will always find foes to conquer in order to maintain their aggressiveness. Long periods of peace are required in order to advance sufficiently for space exploration. Peace has a tendency to soften aggressiveness.
Salvation requires a civilization with vast resources that has nothing to gain or to lose. Yeah, right. Such a civilization cannot evolve, it has no reason to evolve. In the end it becomes just as conservative as an aggressive civilization.
An alien civilization will have it’s aggressiveness, will be prosperous and will have economic interests, They won’t conquer us, but any contact with a more advanced civilization (and a civilization capable of space flight is more advanced then we are) will mean the absorption of their values and the loss of some of our values. We will lose some resources, but probably those resources we don’t know how to use.
All in all, we will win more than we will lose. We will learn faster what we have lost, than we would usually had, see, it’s a win.