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Again, as with most of these speculations, while there are some universalities to inscribe a boundary, there is still much room for a wide range of possibilities.
A fancy way of saying there is much that can be said about this. I can blog on this for years and not exhaust the subject.
For my first preliminary thoughts on this I am reminded about the discussions many scientists have about searching for alien life - we must first look to our own planet for clues. The discovery of extremophiles, life forms that live in extreme conditions (once thought to be inhospitable to life), has forced scientists to expand their search for extraterrestrial life to a wider range of environmental conditions. That is the jumping off point.
So, for outside influence on alien technology, we should first look to our own planet. And what we find is a bit disconcerting. It seems that mankind has evolved technology faster than it has matured to handle it responsibly. Too often we find under our civilized veneer there lies a savage beast. And a beast with access to technology is a terrible beast. And see how often a nation, a group, with higher technology treats another nation with much lower technology, even though both are just as advanced mentally.
Would this be true of most sentient races?
Maybe. Think on this: our planet is, in comparison to other planets, boring. By comparison to most, its axis isn't greatly tilted and doesn't wobble much, it circles its sun in a nearly circular orbit around a fairly consistent sun (compared to many other stars), and because of Jupiter cleaning out many asteroids, may not be as impacted as often as some, or many, extrasolar terrestrial planets. While tectonically active, it is not overly so. However, it has still experienced devastating meteor impacts, super volcanoes, and ice ages interspersed among very tropical ages - all of which puts evolutionary stress on evolving sentience to be a rather adaptive species, and part of that adaptation may mean a certain aggressiveness to explore, spread out, conquer. Only those that fought to survive, survived events and eras that nearly wiped out the rising sentient species of man.
There is genetic evidence that humans have narrowly escaped extinction on more than one occasion. One event, according to the Toba catastrophe theory, involves a super volcano on Sumatra 70,000 to 75,000 years ago which reduced the human population for the entire world down to 2,000 to 10,000 individuals.
So for an extrasolar planet with a more dramatic history caused by its having a more elliptical orbit, greater axial tilt, more tectonic activity, and/or being struck more regularly by meteors, sentient life forms may, out of necessity, be an even more aggressive about ensuring their survival.
Contact by an alien race with higher technology may mean the end of the contacted race - or that they would be subservient to the dominant race and no longer develop their own technology.
Or if such a contact was successfully initially repulsed (whether by luck or by sheer overwhelming numbers), the contacted race would throw all of their energies and will into developing technology to defend themselves from future attacks.
Of course, there are less pessimistic influences... which will be touched upon in posts to follow.
Ambrose, Stanley H. "Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans." Journal of Human Evolution. 34. 1998. 623 - 51.