I think so: if the meeting with a unearthly civilization newcomers will be nonaggressive is necessary to us.
It is connected by that the civilization with a high degree of a conflictness and aggression on the certain level of development will destroy itself. The law of self-preservation of a life in the Universe is those.
The critical point when self-destruction of a civilization becomes inevitable, is reached under the conditions described by me in work "The Formula of the Apocalypse "
By virtue of it, civilizations reached a level on which they are capable to make interstellar flights, with the big degree of probability will be humane. More truly, will appreciate and respect with the right to existence of any forms of a life, especially reasonable. Including and ours.