The risk of a "preemptive" attack by an alien civilization on Earth is quite small, since such an attack is associated with an unavoidable threat of retaliation, the author of an article in Acta Astronautica believes.
Janne Korhonen from Aalto University (Finland) believes that the experience of the Cold War can be useful in assessing the risks of conflicts with extraterrestrial civilizations. Korhonen in his work assesses the risk of a preemptive first strike from the aliens who discovered the Earth, which will be aimed at the complete destruction of earthlings as possible competitors.
The author believes that for truly interstellar civilizations that have mastered more than one planetary system, the possible benefits from such a strike are unlikely to outweigh the risks associated with it. "One-planetary" civilizations, including human, in case of contact, are likely to find themselves in the position of the United States and the USSR during the Cold War, when the threat of guaranteed mutual destruction will deter both sides from the first strike.
“Even if communication is difficult, rational decision-makers will seek to avoid unprovoked attacks, since it is extremely difficult to ensure their success 100%. Overall, it seems likely that interstellar conflicts among civilizations will remain rare,”writes Korhonen.
At the same time, the author of the study warns that any projects of interstellar missions and flights should be treated with caution, since the very fact that earthlings have technology for such travel can be regarded as a threat. In addition, even a simple space probe, once caught in an alien system with intelligent life, can harm it and become a reason for "revenge".
Attempts to communicate with aliens, such as the famous SETI project, Korhonen considers a relatively safe idea, although "especially suspicious civilizations cannot ignore the risk that even harmless messages are a ploy to lure out rivals and preemptively destroy them."
