To an alien without our particular brand of 21st century capital ethics, I'm not sure that the US is winning Civilization Earth.
You don't have to be a threat, just appear as the biggest possible one.
"based on how strong their bows are when you are traveling in a stealth bomber."
One has to know what a bow is and that they only have bows to come to that summary conclusion. If you have no knowledge of the capabilities, caution is warranted - whether we're talking about civilizations or a new species of spider.
Advanced technology != invincibility. Actually, a lot of times the more advanced tech is, the more vulnerable it is to catastrophic failure.
Except we don't use our most powerful energy source (nuclear weapons).
(I’m saying that mostly for the sake of argument, not because I think your reasoning is incorrect.)