Do aliens exist?

[Anomalocaris]

If there is one thing where it can't hurt (much) to be fatalistic, that thing would be a meeting with intelligent, technological aliens. They may or may not be benign. But since the universe is so old, and our experiment with technology comparatively so young, the average technological civilization is likely to be literally billions of years more advanced then we are. In the presence of such a civilization, we can effect nothing. Even the specific powers we attribute to omniscience might be utterly trivial to them. We can not purposely hide from them, since it is unlikely that they would not have already known of us if they are within the range where we have power to effect our visibility. We can not either threaten or befriend them, as both our powers and our friendship would be too far beneath their contempt to influence their actions. We can not defend ourselves, as our greatest defense will not influence the efficacy of their least attack. So aliens ate what they are. If we are curious, we might as well look for them. If they are hostile, they would not have waited this long to harm us.