> [With] Advanced tech...we will certainly kill ourselves off. If the normal developmental pattern of technologically advanced races is T ~ a few thousands of

> [With] Advanced tech...we will certainly kill ourselves off. If the normal developmental pattern of technologically advanced races is T ~ a few thousands of years of continuous population increases due to technology [1], followed by a technology-caused extinction, it would neatly explain why we haven't met any aliens: Since T is a drop in a bucket compared to the time required for evolving intelligence, with high probability all the aliens close enough to us to send signals or spaceships gained intelligence more than T years ago, and have already killed themselves. [1] The exact timing of the beginning of our technological development depends much on how you define "technological development." But it's fairly safe to say that T < 1 million years.