Once cosmic aliens had been discovered it didn’t take long for the forty million or so known forms of intelligent life to work out that basically intelligent life was all the same no matter where they stemmed from in the universe. They were all violent and mean. They were greedy. They were corrupt. They were rotten to the core.
One of the good things about all this however was that weapons of war would not work if they were fired via the instowarpicator. This was a device of extraordinary inventiveness that enabled alien species (I call them “species” but really we need to invent a new word for these divisions)… the instowarpicator enabled each planetary “intelligentis” to travel almost instantaneously from one planet to another.
As I say, lethal weapons of war were neutralized if they travelled down the instowarpicator. Lethal weapons of mass destruction had to travel via the conventional way, that is, through space at the speed of light.
It is believed that almost every planet (if not all) had at some stage fired a destructive weapon at an enemy planet somewhere sometime. The good thing was that the weapons would take thousands (in some cases millions) of light years to reach their targets. This made the inhabitants of every planet blasé about interplanetary co-existence. Each had thousands of years to discover and make an antidote to destructive forces.
So all in all, the cosmos was safe. It’s just that every race of planetary intelligentis hated each other’s guts.