Honestly, I think an easier answer is that intelligent life is simply very rare and interstellar travel is very hard. We may be the only intelligent life withi

Honestly, I think an easier answer is that intelligent life is simply very rare and interstellar travel is very hard. We may be the only intelligent life within our galaxy. Or perhaps just 1 in 100. In either case, it'd take a LONG time before we ever found or met another civilization.